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((short description|Road junction that uses grade separation))
[[File:High Five.jpg|thumb|upright=1.2|The [[High Five Interchange|High Five]] in [[Dallas, Texas]]. This is a complicated five-level stack interchange, due to the proximity of [[frontage road]]s and segregated [[high-occupancy vehicle lane]]s. This hybrid design is based on parts of a four-level stack for highways, with a three-level-diamond interchange to handle the frontage roads.<br />((coord|32|55|27.2|N|96|45|50.0|W))]]

In the field of [[road transport]], an '''interchange''' (American English) or a '''grade-separated junction''' (British English) is a [[road junction]] that uses [[grade separation]]s to allow for the movement of traffic between two or more roadways or [[highway]]s, using a system of interconnecting roadways to permit traffic on at least one of the routes to pass through the junction without interruption from crossing traffic streams. It differs from a standard [[Intersection (road)|intersection]], where roads cross [[wikt:at-grade|at grade]]. Interchanges are almost always used when at least one road is a [[controlled-access highway]] (freeway or motorway) or a [[limited-access road|limited-access divided highway]] (expressway), though they are sometimes used at junctions between surface streets.
[[File:Lakalaivan eritasoliittymä 1.jpg|thumb|An aerial view of the Lakalaiva interchange in the [[Tampere Ring Road]] between the [[Finnish national road 3|Highway 3]] ([[European route E12|E12]]) and [[Finnish national road 9|Highway 9]] ([[European route E63|E63]]) near city of [[Tampere]].<br />((coord|61|27|46|N|23|46|10|E))]]

== Terminology ==
[[File:M0 - 4-es kereszteződés-cropped.png|thumb|An interchange between the [[M0 motorway (Hungary)|M0]] and [[M4 motorway (Hungary)|M4]] motorways outside [[Budapest]], showcases directional, semi-directional, and loop ramps.<br />((coord|47|24|18|N|19|18|55|E))]]
[[File:Light Horse Interchange (aerial view).jpg|thumb|The [[Light Horse Interchange]] in [[Sydney]], the largest in [[Australia]].<ref>((cite web | title = Fact Sheet: Light Horse Interchange&nbsp;– Westlink M7/M4 Motorway Interchange | publisher = Westlink Motorway Limited | date = May 2006 | url = http://www.westlinkm7.com.au/cmsAdmin/uploads/Fact_Sheet_Light_Horse_Interchange.pdf | access-date = July 29, 2021 | archive-url = https://web.archive.org/web/20160303233919/http://www.westlinkm7.com.au/cmsAdmin/uploads/Fact_Sheet_Light_Horse_Interchange.pdf | archive-date = March 3, 2016 | url-status = dead))</ref><br />((coord|33|47|53|S|150|51|15|E))]]

''Note:'' The descriptions of interchanges apply to countries where vehicles [[Left- and right-hand traffic|drive on the right]] side of the road. For left-side driving, the layout of junctions is mirrored. Both North American (NA) and British (UK) terminology is included.

; Freeway junction, highway interchange (NA), or motorway junction (UK)
: A type of road junction linking one controlled-access highway (freeway or motorway) facility to another, to other roads, or to a [[rest area]] or [[motorway service area]]. Junctions and interchanges are often (but not always) numbered either sequentially, or by distance from one terminus of the route (the "beginning" of the route).<ref>((Cite web | title = Interstate System | publisher = Federal Highway Administration | date = February 5, 2019 | url = https://www.fhwa.dot.gov/programadmin/interstate.cfm | access-date = July 27, 2021))</ref>
:The [[American Association of State Highway and Transportation Officials]] (AASHTO) defines an interchange as "a system of interconnecting roadways in conjunction with one or more grade separations that provides for the movement of traffic between two or more roadways or highways on different levels."<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design, 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10.1&nbsp;– Introduction and General Types of Interchanges | year = 2001 | page = 10.1-1<!-- page numbers are based on chapters, this is page 1 of chapter 10.1. Page 863 in PDF --> | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = July 27, 2021 | isbn = 1-56051-156-7))</ref>
; System interchange
: A junction that connects multiple controlled-access highways.<ref name="seh">((cite web | title = The Amazing World of: Interchange Designs | first = Scott | last = Hotchkin | date = 20 March 2017 | publisher = Short Elliott Hendrickson Inc. | url = https://www.sehinc.com/news/amazing-world-interchange-designs | access-date = July 25, 2021))</ref>
; Service interchange
: A junction that connects a controlled-access facility to a lower-order facility, such as an [[arterial road|arterial]] or [[collector road|collector]] road.<ref name="seh" />
: The '''mainline''' is the controlled-access highway in a service interchange, while the '''crossroad''' is the lower-order facility that often includes at-grade intersections or roundabouts, which may pass over or under the mainline.<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design, 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10.8.2&nbsp;– Types of Separation Structures | year = 2001 | page = 10-14<!-- page numbers are based on chapters. Page 876 in PDF --> | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = July 30, 2021 | isbn = 1-56051-156-7))</ref>
; ((anchor|Complete and incomplete interchanges))Complete interchange
: A junction where all possible movements between highways can be made from any direction.<ref name="incomplete">((cite magazine | first1 = James W. | last1 = Epps | first2 = Donald B. | last2 = Stafford | title = Interchange Development Patterns on Interstate Highways in South Carolina | magazine = 53rd Annual Meeting of Highway Research Board, Washington, DC | publisher = Transportation Research Record | year = 1974 | issue = 508 | issn = 0361-1981 | url = http://onlinepubs.trb.org/Onlinepubs/trr/1974/508/508-003.pdf<!-- record: https://trid.trb.org/view/25496 --> | access-date = July 27, 2021))</ref>
; Incomplete interchange
: A junction that is missing at least one movement between highways.<ref name="incomplete" />
; ((anchor|Ramp))Ramp (NA), or slip road (UK/Ireland)
((redirect|Offramp))((redirect2|Slip road|Limited access ramp|the turn lane at an intersection|Slip lane))
: A short section of road that allows vehicles to enter or exit a controlled-access highway.<ref>((cite book | title = Design of Interchange Loop Ramps and Pavement/Shoulder Cross-Slope Breaks | last1 = Torbic | first1 = Darren J. | last2 = Lucas | first2 = Lindsay M. | last3 = Harwood | first3 = Douglas W. | last4 = Brewer | first4 = Marcus A. | last5 = Park | first5 = Eun Sug | last6 = Avelar | first6 = Raul | last7 = Pratt | first7 = Michael P. | last8 = Abu-Odeh | first8 = Akram | last9 = Depwe | first9 = Elizabeth | last10 = Rau | first10 = Kimberly | display-authors = 3 | year = 2017 | publisher = National Academies of Sciences, Engineering, and Medicine|at='''1.1 Background'''. p.((nbsp))18 | doi = 10.17226/24683| isbn = 978-0-309-45554-1))</ref><ref>((cite web | title = Motorways (253 to 273)&nbsp;– Joining the motorway (259) | work = [[The Highway Code]] | publisher = [[Government of the United Kingdom]] | date = June 27, 2014 | url = https://www.gov.uk/motorways-253-to-273/joining-the-motorway-259 | access-date = July 26, 2021))</ref><ref>((cite web | title = Motorways (253 to 273)&nbsp;– Leaving the motorway (272 to 273) | work = [[The Highway Code]] | publisher = [[Government of the United Kingdom]] | date = June 27, 2014 | url = https://www.gov.uk/motorways-253-to-273/leaving-the-motorway-272-to-27 | access-date = July 26, 2021 ))((Dead link|date=January 2023 |bot=InternetArchiveBot |fix-attempted=yes ))</ref><ref name="Ireland">((cite report | title = The Design of Major Interchanges | publisher = Transport Infrastructure Ireland | date = December 2020 | id = DN-GEO-03041 | page = 6-1<!-- PDF page 39 --> | url = https://www.tiipublications.ie/library/DN-GEO-03041-01.pdf | access-date = August 1, 2021))</ref>
:''Ingressing'' traffic is entering the highway via an '''on-ramp''' or '''entrance ramp''', while ''egressing'' traffic is exiting the highway via an '''off-ramp''' or '''exit ramp'''.<ref>((cite web | title = Ingress/Egress | publisher = Texas Department of Transportation | url = https://www.txdot.gov/driver/txdot-visual-dictionary/ingress-egress.html | access-date = July 18, 2021 | archive-date = July 18, 2021 | archive-url = https://web.archive.org/web/20210718204323/https://www.txdot.gov/driver/txdot-visual-dictionary/ingress-egress.html | url-status = dead ))</ref>
; Directional ramp
: A ramp that curves toward the desired direction of travel; i.e., a ramp that makes a left turn exits from the left side of the roadway (a left exit).<ref name="iowadotgov">((cite web | author = Iowa Department of Transportation | author-link = Iowa Department of Transportation | title = Cross Sections of One-Way Ramps and Loops | date = September 1, 1995 | url = http://www.iowadot.gov/design/dmanual/06b-01.pdf | access-date = October 19, 2009))</ref>
; Semi-directional ramp
: A ramp that exits in a direction opposite from the desired direction of travel, then turns toward the desired direction. Most left turn movements are provided by a semi-directional ramp that exits to the right, rather than exiting from the left.<ref name="iowadotgov" />
; [[Grade separation#Weaving|Weaving]]
: An undesirable situation where traffic entering and exiting a highway must cross paths within a limited distance.<ref>((cite report | title = Guidelines for Ramp and Interchange Spacing | author = National Cooperative Highway Research Program, Transportation Research Board | publisher = National Academy of Sciences | year = 2011 | section = 4.2.3 Weaving Segments | pages = 45–46 | isbn = 978-0-309-15548-9 | url = http://www.cmfclearinghouse.org/studydocs/nchrp_rpt_687.pdf | access-date = July 27, 2021))</ref>
((clear))

== History ==
The concept of the controlled-access highway developed in the 1920s and 1930s in Italy, Germany, the United States, and Canada. Initially, these roads featured at-grade intersections along their length. Interchanges were developed to provide access between these new highways and heavily-travelled surface streets. The [[Bronx River Parkway]] and [[Long Island Motor Parkway]] were the first roads to feature grade-separations.((refn |group=lower-alpha |With the [[Bronx River Parkway]] being the first to start construction ((refn |group=lower-alpha |Started 1907,<ref name="DOT on the Bronx River Parkway">((cite web|title=Bronx River Parkway|url=https://www.dot.ny.gov/display/programs/scenic-byways/bronx-river-pkwy|website=www.dot.ny.gov|publisher=New York Department of Transportation|access-date=4 October 2014|url-status=dead|archive-url=https://web.archive.org/web/20160304221626/https://www.dot.ny.gov/display/programs/scenic-byways/bronx-river-pkwy|archive-date=4 March 2016))</ref> opened 1922.<ref>((cite news |title=City Opens Bronx Park Way to Traffic |url=https://www.nytimes.com/1922/09/17/archives/city-opens-bronx-park-way-to-traffic-provides-unbroken-highway-from.html |newspaper=[[The New York Times]] |date=September 17, 1922 |page=14 |access-date=April 13, 2010))</ref>)) and the [[Long Island Motor Parkway]] being first to open ((refn |group=lower-alpha |Started June 1908,<ref>((cite news |url=http://www.newsday.com/community/guide/lihistory/ny-history-hs701a%2C0%2C106290%2Cprint.story |title=The Age of the Auto: Sportsman William K. Vanderbilt II's cup race paves the way to the future |last=Adcock |first=Sylvia |date=April 12, 1998 |page=A16 |work=[[Newsday]]|archiveurl=https://web.archive.org/web/20050131204720/http://www.newsday.com/community/guide/lihistory/ny-history-hs701a,0,106290,print.story |archivedate=January 31, 2005 |url-status=dead))</ref> opened October 10, 1908.<ref name="nyt-1908-10-10">((cite news|title=35 cars to race on the Motor Parkway|url=https://timesmachine.nytimes.com/timesmachine/1908/10/10/104760606.pdf|newspaper=The New York Times|date=October 10, 1908|page=10|archiveurl=https://web.archive.org/web/20181001195717/https://timesmachine.nytimes.com/timesmachine/1908/10/10/104760606.pdf|archivedate=October 1, 2018 |url-status=live))</ref>)).))<ref>((cite news | title = Built to Meander, Parkway Fights to Keep Measured Pace | work = [[New York Times]] | date = June 6, 1995 | url = https://www.nytimes.com/1995/06/06/nyregion/built-to-meander-parkway-fights-to-keep-measured-pace.html | access-date = August 1, 2021))</ref><ref name="evolution">((cite report | title = Evolution of Interchange Design in North America | first1 = Joel P. | last1 = Leisch | first2 = John | last2 = Morrall | publisher = Conference of the Transportation Association of Canada | year = 2014 | url = http://conf.tac-atc.ca/english/annualconference/tac2014/s-30/morrall.pdf | access-date = July 29, 2021))</ref>
[[Maryland]] engineer Arthur Hale filed a patent for the design of a cloverleaf interchange on May((nbsp))24, 1915,<ref name="hale">((cite web | title = US Patent No. 1173505A | publisher = Google Patents | url = https://patents.google.com/patent/US1173505A/en | access-date = July 29, 2021))</ref>
though the conceptual roadwork was not realised until a cloverleaf opened on December((nbsp))15, 1929, in [[Woodbridge Township, New Jersey|Woodbridge, New Jersey]], connecting [[New Jersey Route&nbsp;25]] and [[New Jersey Route 4|Route&nbsp;4]] (now [[U.S. Route&nbsp;1/9]] and [[New Jersey Route&nbsp;35]]). It was designed by [[Philadelphia]] engineering firm Rudolph and Delano, based on a design seen in an Argentinian magazine.<ref name="LAtimes">((cite news | title = A Major Lane Change | first = Hugo | last = Martin | date = April 7, 2004 | newspaper = [[LA Times]] | url = http://articles.latimes.com/2004/apr/07/local/me-cloverleaf7 | archive-url = https://web.archive.org/web/20120112114913/http://articles.latimes.com/2004/apr/07/local/me-cloverleaf7 | archive-date = January 12, 2012 | access-date = July 29, 2021))</ref><ref name="Courier">((cite news | title = New Bridge Over Raritan, 'Express Route' Opens Today | work = [[Courier-Post]] | location = Camden, New Jersey | date = December 15, 1929 | page = 23 | url = https://www.newspapers.com/clip/82447195/first-cloverleaf-interchange-opens/ | access-date = July 29, 2021))</ref><ref name="evolution" />

((clear|right))
<!-- storing images here
[[File:Wezelsosnicafromthesky.JPG|thumb|The [[Gliwice]]-Sośnica interchange, Poland.<ref>[http://www.gddkia.gov.pl/pl/a/3623/podpisano-umowe-na-najwiekszy-wezel-autostradowy-w-europie Podpisano umowę na największy węzeł autostradowy w Europie] ((in lang|pl))</ref> ((coord|50.261249|N|18.720944|E))]]-->

== System interchange ==
((comparison_of_four_legged_interchanges.svg))
A system interchange connects multiple controlled-access highways, involving no at-grade signalised intersections.<ref name="seh" />
=== Four-legged interchanges ===
==== Cloverleaf interchange ====
((main article|Cloverleaf interchange))
[[File:APD-40cloverleaf.jpg|thumb|A full cloverleaf interchange between [[APD-40]] and [[U.S. Route 64]] near [[Cleveland, Tennessee]] ((coord|35|08|59.4|N|84|50|52.3|W))]]
A cloverleaf interchange is a four-legged junction where left turns across opposing traffic are handled by non-directional loop ramps.<ref name="zhong">((cite thesis | first = Hantao | last = Zhong | title = Free-flow Parclo Interchange vs. the Cloverleaf Interchange with C-D Roads and the All-Directional Four-level Interchange: A Comparison of Geometrics, Construction Cost, and Right of Way Requirements | publisher = North Carolina State University | year = 2012 | place = Raleigh, North Carolina | url = https://repository.lib.ncsu.edu/bitstream/handle/1840.16/8006/etd.pdf?sequence=2&isAllowed=y | access-date = July 31, 2021))</ref>
It is named for its appearance from above, which resembles a [[four-leaf clover]].<ref name="LAtimes" />
A cloverleaf is the minimum interchange required for a four-legged system interchange. Although they were commonplace until the 1970s, most highway departments and ministries have sought to rebuild them into more efficient and safer designs.<ref name="zhong" /> 
The cloverleaf interchange was invented by Maryland engineer Arthur Hale, who filed a patent for its design on May((nbsp))24, 1915.<ref name="hale" />
The first one in North America opened on December((nbsp))15, 1929, in Woodbridge, New Jersey, connecting New Jersey Route((nbsp))25 and Route((nbsp))4 (now U.S. Route((nbsp))1/9 and New Jersey Route((nbsp))35). It was designed by Philadelphia engineering firm Rudolph and Delano based on a design seen in an Argentinian magazine.<ref name="LAtimes" /><ref name="Courier" />

The first cloverleaf in Canada opened in 1938 
at the junction of [[Ontario Highway 10|Highway&nbsp;10]] and what would become the [[Queen Elizabeth Way]].<ref>((cite book | title = From Footpaths to Freeways | first1 = John | last1 = Shragge | first2 = Sharon | last2 = Bagnato | publisher = Ontario Ministry of Transportation and Communications, Historical Committee | year = 1984 | pages = 79–81 | isbn = 0-7743-9388-2))</ref>
The first cloverleaf outside of North America opened in [[Stockholm]] on October((nbsp))15, 1935. Nicknamed [[Slussenområdet|Slussen]], it was referred to as a "traffic carousel" and was considered a revolutionary design at the time of its construction.<ref>((cite news | title = The octopus that could save Slussen | first = Solveig | last = Rundquist | publisher = The Local | location = Sweden | date = June 17, 2014 | language = en | url = https://www.thelocal.se/20140617/the-octopus-that-saved-slussen/ | access-date = July 19, 2021))</ref>

A cloverleaf offers uninterrupted connections between two roads but suffers from weaving issues. Along the mainline, a loop ramp introduces traffic prior to a second loop ramp providing access to the crossroad, between which ingress and egress traffic mixes. For this reason, the cloverleaf interchange has fallen out of favour in place of [[#Combination interchange|combination interchanges]].<ref name="LAtimes" /> Some may be half cloverleaf containing [[ghost ramps]] which can be upgraded to full cloverleafs if the road is extended. [[U.S. Route 70 in North Carolina |US 70]] and [[U.S. Route 17 in North Carolina |US 17]] west of [[New Bern, North Carolina]] is an example.
((Clear))

==== Stack interchange ====
((unsourced section|date=June 2022))
((main article|Stack interchange))

[[File:Shanghai, China (Unsplash).jpg|thumb|A multi-level stack interchange in [[Jing'an District|Jing'an]], Shanghai, China. ((coord|31|13|27.7|N|121|28|09.0|E))]]
A stack interchange is a four-way interchange whereby a semi-directional left turn and a directional right turn are both available. Usually, access to both turns is provided simultaneously by a single off-ramp. Assuming right-handed driving, to cross over incoming traffic and go left, vehicles first exit onto an off-ramp from the rightmost lane. After demerging from right-turning traffic, they complete their left turn by crossing both highways on a flyover ramp or underpass. The penultimate step is a merge with the right-turn on-ramp traffic from the opposite quadrant of the interchange. Finally, an on-ramp merges both streams of incoming traffic into the left-bound highway. As there is only one off-ramp and one on-ramp (in that respective order), stacks do not suffer from the problem of weaving, and due to the semi-directional flyover ramps and directional ramps, they are generally safe and efficient at handling high traffic volumes in all directions.

A standard stack interchange includes roads on four levels, also known as a 4-level stack, including the two perpendicular highways, and one more additional level for each pair of left-turn ramps. These ramps can be stacked (cross) in various configurations above, below, or between the two interchanging highways. This makes them distinct from turbine interchanges, where pairs of left-turn ramps are separated but at the same level. There are some stacks that could be considered 5-level; however, these remain four-way interchanges, since the fifth level actually consists of dedicated ramps for [[High-occupancy vehicle lane|HOV]]/bus lanes or frontage roads running through the interchange. The stack interchange between I-10 and I-405 in [[Los Angeles]] is a 3-level stack, since the semi-directional ramps are spaced out far enough, so they do not need to cross each other at a single point as in a conventional 4-level stack.

Stacks are significantly more expensive than other four-way interchanges are due to the design of the four levels; additionally, they may suffer from objections of local residents because of their height and high visual impact. Large stacks with multiple levels may have a complex appearance and are often colloquially described as ''Mixing Bowls'', ''[[Stack interchange|Mixmasters]]'' (for a [[Sunbeam Products]] brand of electric kitchen [[mixer (cooking)|mixer]]s), or as ''Spaghetti Bowls'' or ''[[Spaghetti Junction]]s'' (being compared to boiled [[spaghetti]]). However, they consume a significantly smaller area of land compared to a cloverleaf interchange.
((Clear))

==== Combination interchange ====
((anchor|Combination interchange))
[[File:CloverStackIntersection.svg|thumb|Cloverstack Interchange]]
A combination interchange (sometimes referred to by the portmanteau, ''cloverstack'')<ref>((cite web | url = https://www.nh.gov/dot/org/projectdevelopment/environment/units/project-management/documents/August162017Minutes-FINAL.pdf | title = Bureau of Environment Conference Report: NHDOT Monthly Natural Resource Agency Coordination Meeting | publisher = [[New Hampshire Department of Transportation]] | date = August 16, 2017 | access-date = August 5, 2021))</ref><ref>((cite web | url = https://dublinohiousa.gov/dev/dev/wp-content/uploads/2015/02/Ord-12-15.pdf | title = Ordinance No. 12-15 | last = McDaniel | first = Dana L. | publisher = City of [[Dublin, Ohio]] | date = February 5, 2015 | access-date = August 5, 2021))</ref> is a hybrid of other interchange designs. It uses loop ramps to serve slower or less-occupied [[traffic flow]], and flyover ramps to serve faster and heavier traffic flows.<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design, 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10&nbsp;– Grade Separations and Interchanges | year = 2001 | pages = 803–805 | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = July 10, 2021 | isbn = 1-56051-156-7))</ref><ref>((cite book | title = Publication 13M&nbsp;– Design Manual, Part 2 Highway Design, Chapter 4 | publisher = [[Pennsylvania Department of Transportation]] | date = April 2021 | edition = 6 | page = 4-4 | url = http://www.dot.state.pa.us/public/pubsforms/Publications/PUB%2013M/April%202021%20Change%20No.%206.pdf | access-date = July 10, 2021))</ref>
If local and express ways serving the same directions and each roadway is connected righthand to the interchange, extra ramps are installed. The combination interchange design is commonly used to upgrade cloverleaf interchanges to increase their capacity and eliminate weaving.<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design, 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10&nbsp;– Grade Separations and Interchanges | year = 2001 | pages = 10-72–10-76<!-- PDF pages 934–938 --> | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = August 3, 2021 | isbn = 1-56051-156-7))</ref> 

((Clear))

==== Turbine interchange ====
((multiple image
| align     = left

| image1    = Knooppunt turbine.png
| width1    = 100
| caption1  = Two-level turbine

| image2    = Knooppunt sterturbine.png
| width2    = 100
| caption2  = Turbine-stack<br />hybrid

| footer =
Some two-level turbines:
* [[Lummen]], Belgium,<ref>((cite web|title=Turbine Interchange Analysis in Lummen|publisher=[[Jan De Nul Group]]|url=https://www.jandenul.com/projects/cloverleaf-interchange-lummen-belgium|access-date=July 13, 2021))</ref> ((nowrap|((coord|50.9994|N|5.2236|E|))))
* [[Jacksonville, Florida]], US,<ref>((cite web|title=I-94 East Metro Interchange Study|publisher=[[Minnesota Department of Transportation]]|url=https://i-94-east-metro-interchange-study-wsbeng.hub.arcgis.com/pages/example-interchanges|access-date=July 13, 2021|via=ArcGIS))</ref> ((nowrap|((coord|30.2531|N|81.5163|W))))
* [[Charlotte, North Carolina]], US,<ref>((cite web|title=I-485/I-85 Turbine Interchange Design-Build|publisher=[[STV Inc.]]|url=https://www.stvinc.com/project/i-485i-85-turbine-interchange-design-build|access-date=July 13, 2021))</ref> ((nowrap|((coord|35.3482|N|80.7335|W))))
* [[Amarillo, Texas]], US,<ref>((cite magazine|title=The art of the interchange|first=Peter|last=Andrew|magazine=[[Politico]]|date=July 22, 2015|url=https://www.politico.com/magazine/gallery/2015/07/the-art-of-the-interchange-000173/?slide=7|access-date=July 13, 2021))</ref> ((nowrap|((coord|35.1929|N|101.8371|W))))
Some turbine-stack hybrids:
* [[Warren, Michigan]], US, ((nowrap|((coord|42.4879|N|83.0457|W))))
* [[Town and Country, Missouri]], US, ((nowrap|((coord|38.6386|N|90.4497|W))))
))
[[File:Autobunnskräiz-RO-A201_cropped.jpg|thumb|A turbine interchange between [[A201 road (Belgium)|A201]] and the [[Brussels Ring]] (R0) in [[Brussels]]<br />((coord|50|53|30.1|N|4|27|15.3|E))]]
The '''turbine interchange''' is an alternative four-way directional interchange. The turbine interchange requires fewer levels (usually two or three) while retaining directional ramps throughout. It features right-exit, left-turning ramps that sweep around the center of the interchange in a clockwise [[spiral]]. A full turbine interchange features a minimum of 18 overpasses, and requires more land to construct than a four-level stack interchange; however, the bridges are generally short in length. Coupled with reduced maintenance costs, a turbine interchange is a less costly alternative to a stack.<ref>((cite web|title=Rare 'Turbine' Design for Charlotte's I-85/485 Interchange|first=Jim|last=Parsons|date=May 23, 2012|website=ENR Southeast|url=https://www.enr.com/articles/12107-rare-turbine-design-for-charlotte-s-i-85-485-interchange|access-date=July 13, 2021))</ref>

((Clear))

==== Windmill interchange ====
((OR section|date=February 2022))

[[File:Vaanplein1997.jpeg|thumb|The ((ill|Vaanplein|nl|Knooppunt Vaanplein)) junction in [[Barendrecht]], Netherlands was a windmill before it was renovated in 1977.<br />((coord|51.8654|N|4.5154|E))]]
A windmill interchange is similar to a turbine interchange, but it has much sharper turns, reducing its size and capacity. The interchange is named for its similar overhead appearance to the blades of a [[windmill]].

A variation of the windmill, called the diverging windmill, increases capacity by altering the direction of traffic flow of the interchanging highways, making the connecting ramps much more direct.<ref>((cite web | url = https://nmcdn.io/e186d21f8c7946a19faed23c3da2f0da/8bfec28a290449a7b10eb1fee3a0e264/files/programs-studies/hot-spots/Final_CAMPO_I-40-US_1_Hotspot_Assessment_Report.pdf | title = I-40 AT I-440/ US 1/ US 64 Interchange Feasibility Study, Prepared for: North Carolina Capital Area Metropolitan Planning Organization | publisher = [[WSP USA|Parsons Brinckerhoff]] | date = August 2015 | accessdate = January 5, 2022))</ref> There also is a [[#Hybrid interchanges|hybrid interchange]] somewhat like the diverging windmill in which left turn exits merge on the left, but it differs in that the left turn exits use left directional ramps.
((clear))

==== Braided interchange ====
((anchor|Combination interchange))[[File:I-95_and_695_Interchange_Baltimore.jpg|thumb|A diverging interchange at I-95 and I-695 in [[Baltimore]] in 1998.]]A '''braided''' or diverging '''interchange''' is a two-level, four-way interchange. An interchange is braided when at least one of the roadways reverses sides. It seeks to make left and right turns equally easy.<ref>((Cite web |title=Dror Bar-Natan's Image Gallery: Knotted Objects: Baltimore Interchange |url=http://www.math.toronto.edu/~drorbn/Gallery/KnottedObjects/Interchange/index.html |access-date=2022-05-02 |website=www.math.toronto.edu))</ref> In a pure braided interchange, each roadway has one right exit, one left exit, one right on-ramp, and one left on-ramp, and both roadways are flipped. 

The first pure braided interchange was built in [[Baltimore]] at [[Interstate 95 in Maryland|Interstate 95]] at [[Interstate 695 (Maryland)|Interstate 695]];<ref>((Cite web |last=Manaugh |first=Geoff |date=2005-12-29 |title=The knot driver |url=https://bldgblog.com/2005/12/the-knot-driver/ |url-status=live |archive-url=https://web.archive.org/web/20220503003328/https://bldgblog.com/2005/12/the-knot-driver/ |archive-date=2022-05-03 |access-date=2022-05-03))</ref> however, the interchange was reconfigured in 2008 to a traditional stack interchange.<ref>((Cite web |last=Lookingbill |first=Amy P. |title=Construction still rolling along I-95 to prepare for Express Toll Lanes |url=https://www.avenuenews.com/news/construction-still-rolling-along-i-95-to-prepare-for-express-toll-lanes/article_57a9e489-5d59-5858-b853-232e66d6494b.html |access-date=2022-05-03 |website=The Avenue News |date=3 July 2007 |language=en))</ref>

;Examples

* [[Interstate 65 in Alabama|Interstate 65]] and [[Interstate 20 in Alabama|Interstate 20]]/[[Interstate 59]] in [[Birmingham, Alabama]] (((Coordinates|33.521414|-86.826513)))
* [[Interstate 196]] and [[U.S. Route 131]] in [[Grand Rapids, Michigan]] (((Coordinates|42.972487|-85.677781)))
* [[Interstate 77 in North Carolina|Interstate 77]] and [[Interstate 85 in North Carolina|Interstate 85]] in [[Charlotte, North Carolina]] (((Coordinates|35.272967|-80.845550)))
* Eastern Ring Road and Southern Ring Branch Road, [[Riyadh]] (((Coordinates|24.631542|46.803334)))((Clear))

==== Three-level roundabout ====
((main article|Roundabout interchange))
((multiple image
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| image1    = Knooppunt rotonde2.png
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| caption1  = Two level roundabout<br />((coord|50.556257|n|7.248577|e))

| image2    = Knooppunt_rotonde3.png
| width2    = 100
| caption2  = Three level roundabout<br />((coord|52.384416|n|4.707492|e))
| 
))[[File:Kleinpolderplein.jpeg|thumb|Complex roundabout interchange ''Kleinpolderplein'' in Rotterdam, the [[Netherlands]]. ((coord|51.931498|n|4.438479|e))]]
A three-level roundabout interchange features a grade-separated roundabout which handles traffic exchanging between highways.<ref name="Ireland" />
The ramps of the interchanging highways meet at a [[roundabout]], or rotary, on a separated level above, below, or in the middle of the two highways.
((clear))

=== Three-legged interchanges ===
((OR section|date=July 2021))
These interchanges can also be used to make a "linking road" to the destination for a service interchange, or the creation of a new basic road as a service interchange.

==== Trumpet interchange ====
[[File:Ottawa River Parkway interchange.jpg|thumb|A trumpet interchange on the [[Kichi Zibi Mikan]] (former John A. Macdonald) Parkway in [[Ottawa]], Ontario<br />((coord|45|24|41|N|75|44|7|W))]]
Trumpet interchanges may be used where one highway terminates at another highway, and are named as such for to their resemblance to [[trumpet|trumpets]]. They are sometimes called ''jug handles''.<ref>((cite report | title = 2013 Design Manual | publisher = Indiana Department of Transportation | year = 2013 | chapter = 48 | page = 69 | chapter-url = https://www.in.gov/dot/div/contracts/design/Part%203/Chapter%2048%20-%20Interchanges.pdf | access-date = August 3, 2021))</ref>

These interchanges are very common on [[toll roads]], as they concentrate all entering and exiting traffic into a single stretch of roadway, where toll plazas can be installed once to handle all traffic, especially on [[ticket system|ticket-based tollways]]. A double-trumpet interchange can be found where a toll road meets another toll road or a free highway. They are also useful when most traffic on the terminating highway is going in the same direction. The turn that is used less often would contain the slower loop ramp.<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design, 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10&nbsp;– Grade Separations and Interchanges | year = 2001 | page = 10-32<!-- PDF page 10-32 --> | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = August 3, 2021 | isbn = 1-56051-156-7))</ref>

Trumpet interchanges are often used instead of directional or semi-directional T or Y interchanges because they require less bridge construction but still eliminate weaving.((Citation needed|date=February 2022))((Clear))

==== T and Y interchanges ====
((anchor|Semi-directional T interchange|Directional T interchange (Y-interchange)|Directional_T_interchange))
[[Image:Knooppunt driehoek.png|thumb|left|100px|Full Y]]
[[Image:California SR 85 and SR 87 Interchange.jpg|thumb|Complex T interchange of SR 85 and SR 87 in [[San Jose, California]]. ((coord|37.255721|N|121.858878|W))]]
'''A full Y-interchange''' (also known as a directional T interchange) is typically used when a three-way interchange is required for two or three highways interchanging in semi-parallel/perpendicular directions, but it can also be used in right-angle case as well. Their connecting ramps can spur from either the right or left side of the highway, depending on the direction of travel and the angle.

Directional T interchanges use flyover/underpass ramps for both connecting and mainline segments, and they require a moderate amount of land and moderate costs since only two levels of roadway are typically used. Their name derives from their resemblance to the capital letter T, depending upon the angle from which the interchange is seen and the alignment of the roads that are interchanging. It is sometimes known as the "New England Y", as this design is often seen in the northeastern United States, particularly in Connecticut. <ref>((cite web |last1=Milano |first1=Lou |title=CT Has an Absurd Number of Left Exits, the Most in New England by far |url=https://i95rock.com/ct-has-an-absurd-amount-of-left-exits-the-most-in-new-england-by-far/ |website=I95 Rock|date=4 March 2022 ))</ref>

This type of interchange features directional ramps (no loops, or weaving right to turn left) and can use multilane ramps in comparatively little space. Some designs have two ramps and the "inside" through road (on the same side as the freeway that ends) crossing each other at a three-level bridge. The directional T interchange is preferred to a trumpet interchange because a trumpet requires a loop ramp by which speeds can be reduced, but flyover ramps can handle much faster speeds. The disadvantage of the directional T is that traffic from the terminating road enters and leaves on the passing lane, so the semi-directional T interchange (see below) is preferred.

The interchange of [[Ontario Highway 416|Highway&nbsp;416]] and [[Ontario Highway 417|Highway&nbsp;417]] in Ontario, constructed in the early 1990s, is one of the few directional T interchanges, as most transportation departments had switched to the semi-directional T design.

[[Image:Interchange-colour-img 0526.jpg|thumb|Two level semi-directional T interchange in [[Orbe, Switzerland]]. ((coord|46.72836|N|6.569738|E))]]
As with a directional T interchange, '''a semi-directional T interchange''' uses [[Overpass|flyover]] (overpass) or [[Tunnel|underpass]] ramps in all directions at a three-way interchange. However, in a semi-directional T, some of the splits and merges are switched to avoid ramps to and from the [[passing lane]], eliminating the major disadvantage of the directional T. Semi-directional T interchanges are generally safe and efficient, though they do require more land and are costlier than trumpet interchanges.
[[File:Knooppunt halve ster.png|left|thumb|Semi-directional T interchange]]
Semi-directional T interchanges are built as two- or three-level junctions, with three-level interchanges typically used in urban or suburban areas where land is more expensive. In a three-level semi-directional T, the two semi-directional ramps from the terminating highway cross the surviving highway at or near a single point, which requires both an overpass and underpass. In a two-level semi-directional T, the two semi-directional ramps from the terminating highway cross each other at a different point than the surviving highway, necessitating longer ramps and often one ramp having two overpasses. [[Ontario Highway 412|Highway&nbsp;412]] has a three-level semi-directional T at [[Ontario Highway 407|Highway&nbsp;407]] and a two-level semi-directional T at [[Ontario Highway 401|Highway&nbsp;401]].

((clear|left))

== Service interchange ==
Service interchanges are used between a [[controlled-access highway|controlled-access route]] and a crossroad that is not controlled-access. A full cloverleaf may be used as a system or a service interchange.<ref name="zhong" />

=== Diamond interchange ===
((main article|Diamond interchange))
[[File:Florida SR 408 at SR 435.jpg|thumb|A typical diamond interchange, located at the junction of [[Florida State Road 435]] and the [[Florida State Road 408|Spessard L. Holland East–West Expressway]]<br />((coord|28|32|56.3|N|81|27|25.9|W))]]
A diamond interchange is an interchange involving four ramps where they enter and leave the freeway at a small angle and meet the non-freeway at almost right angles. These ramps at the non-freeway can be controlled through [[stop sign]]s, [[traffic light|traffic signals]], or turn ramps.

Diamond interchanges are much more economical in use of materials and land than other interchange designs, as the junction does not normally require more than one bridge to be constructed. However, their capacity is lower than other interchanges and when traffic volumes are high they can easily become congested.

((clear|left))

;Double roundabout diamond
((anchor|dogbone))((anchor|dumbbell))
[[File:Holt Road Dogbone.png|thumb|left|A dumbbell interchange along [[Ontario Highway 401]] in [[Clarington]]<br />((coord|43|53|3|N|78|43|20|W))]]
A double roundabout diamond interchange, also known as a dumbbell interchange or a dogbone interchange, is similar to the diamond interchange, but uses a pair of roundabouts in place of intersections to join the highway ramps with the crossroad. This typically increases the efficiency of the interchange when compared to a diamond, but is only ideal in light traffic conditions. In the dogbone variation, the roundabouts do not form a complete circle, instead having a [[wiktionary:teardrop|teardrop]] shape, with the points facing towards the center of the interchange. Longer ramps are often required due to line-of-sight requirements at roundabouts.<ref>((cite report | title = South Carolina Roadway Design Manual | publisher = [[South Carolina Department of Transportation]] | date = February 2021 | section = 10.2.7 Double Roundabout Diamond | at = pp.((nbsp))10.2-7–10.2-8<!-- page numbers are based on chapters. Pages 17–18 in PDF --> | url = https://www.scdot.org/business/pdf/roadway/revisedChapters/Chapter%2010%20-%20Interchanges.pdf | access-date = July 30, 2021))</ref>
((clear|left))

=== Partial cloverleaf interchange ===
((Main|Partial cloverleaf interchange))
[[File:Derry and 407.jpg|thumb|A parclo A4 interchange along [[Ontario Highway 407|Highway&nbsp;407]] on the [[Mississauga]] / [[Milton, Ontario]], boundary<br />((coord|43|34|17.8|N|79|47|23.6|W))]]
[[File:Autobahn anschluss1.jpg|thumb|A parclo AB2, or ''folded-diamond'' interchange along [[Bundesautobahn 7]] in Germany<br />((coord|47|38|28.68|N|10|31|40.08|E))]]
A partial cloverleaf interchange (often shortened to the portmanteau, ''parclo'') is an interchange with loops ramps in one to three quadrants, and diamond interchange ramps in any number of quadrants. The various configurations are generally a safer modification of the cloverleaf design, due to a partial or complete reduction in weaving, but may require traffic lights on the lesser-travelled crossroad. Depending on the number of ramps used, they take up a moderate to large amount of land, and have varying capacity and efficiency.<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design | year = 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10.9.3.6.1&nbsp;– Partial Cloverleaf Ramp Arrangements | at = pp.((nbsp))10-60–10-63<!-- page numbers are based on chapters. Pages 922–925 in PDF --> | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = July 27, 2021 | isbn = 1-56051-156-7))</ref>

Parclo configurations are given names based on the location of and number of quadrants with ramps. The letter ''A'' denotes that, for traffic on the [[controlled-access highway]], the loop ramps are located in ''advance'' of (or ''approaching'') the crossroad, and thus provide an onramp to the highway. The letter ''B'' indicated that the loop ramps are ''beyond'' the crossroad, and thus provide an offramp from the highway. These letters can be used together when opposite directions of travel on the controlled-access highway are not symmetrical, thus a parclo AB features a loop ramp approaching the crossroad in one direction, and beyond the crossroad in the opposing direction, as in the example image.<ref>((cite report | title = South Carolina Roadway Design Manual | publisher = [[South Carolina Department of Transportation]] | date = February 2021 | section = 10.2.10 Partial Cloverleafs | at = pp.((nbsp))10.2-11–10.2-12<!-- page numbers are based on chapters. Pages 22–23 in PDF --> | url = https://www.scdot.org/business/pdf/roadway/revisedChapters/Chapter%2010%20-%20Interchanges.pdf | access-date = July 27, 2021))</ref>

((-))

=== Diverging diamond interchange ===
((main article|Diverging diamond interchange))
[[File:Camp Creek at I-285 Aerial (50924270112).jpg|thumb|A diverging diamond at [[Interstate 285 (Georgia)|Interstate&nbsp;285]] and [[Camp Creek Parkway]] near [[Atlanta]]<br>((coord|33|39|23.5|N|84|29|51.5|W))]]
A [[diverging diamond interchange]] (DDI) or double crossover diamond interchange (DCD) is similar to a traditional diamond interchange, except the opposing lanes on the crossroad cross each other twice, once on each side of the highway. This allows all highway entrances and exits to avoid crossing the opposite direction of travel and saves one signal phase of traffic lights each.<ref>((cite web | first1 = Warren | last1 = Hughes | first2 = Ram | last2 = Jagannathan | title = Double Crossover Diamond Interchange | id = FHWA-HRT-09-054 | publisher = [[Federal Highway Administration]] | date = October 2009 | url = http://www.fhwa.dot.gov/publications/research/safety/09054/index.cfm | access-date = July 30, 2021))</ref>

The first DDIs were constructed in the [[France|French]] communities of [[Versailles (city)|Versailles]] ([[A13 autoroute|A13]] at D182), [[Le Perreux-sur-Marne]] ([[A4 autoroute|A4]] at N486) and [[Seclin]] ([[A1 autoroute (France)|A1]] at D549), in the 1970s.<ref>((cite web | author = Staff | title = I-64 Interchange at Route 15, Zion Crossroads | publisher = [[Virginia Department of Transportation]] | date = June 13, 2013 | url = http://www.virginiadot.org/projects/culpeper/zioncrossroads.asp | access-date = July 30, 2021 | archive-url = https://web.archive.org/web/20131127125317/http://www.virginiadot.org/projects/culpeper/zioncrossroads.asp | archive-date = November 27, 2013 | url-status = dead))</ref> Despite the fact that such interchanges already existed, the idea for the DDI was "reinvented" around 2000, inspired by the freeway-to-freeway interchange between [[Interstate 95]] and [[Interstate 695 in Maryland|I-695]] north of [[Baltimore]].<ref>((cite web |first = Gilbert | last = Chlewicki |title = New Interchange and Intersection Designs: The Synchronized Split-Phasing Intersection and the Diverging Diamond Interchange |year = 2003 |url = http://www.urbanstreet.info/2nd_sym_proceedings/Volume%202/Chlewicki.pdf |url-status = dead |archive-url = https://wayback.archive-it.org/all/20111020071633/http://www.urbanstreet.info/2nd_sym_proceedings/Volume%202/Chlewicki.pdf |access-date = October 20, 2009 |archive-date = October 20, 2011))</ref> The first DDI in the United States opened on July((nbsp))7, 2009, in [[Springfield, Missouri]], at the junction of [[Interstate 44]] and [[Missouri Route 13]].<ref>((cite web |url=http://www.modot.org/southwest/major_projects/Greene/documents/I-44-Route13DDI.pdf |title=Missouri Department of Transportation))</ref><ref>((cite web |author= Staff |url= http://www.modot.org/springfield/major_projects/Greene/I-44andRoute13.html |title= I-44/Route 13 Interchange Reconstruction: Diverging Diamond Design |date= June 2011 |access-date= October 3, 2015 |publisher= [[Missouri Department of Transportation]] |archive-url= https://web.archive.org/web/20110607123620/http://www.modot.org/springfield/major_projects/Greene/I-44andRoute13.html |archive-date= June 7, 2011))</ref>((clear))

=== Single-point urban interchange ===
((main article|Single-point urban interchange))
[[File:I-84 Meridian Interchange.jpg|thumb|Single-point urban interchange along [[Interstate 84 in Idaho|Interstate 84]] in [[Meridian, Idaho]], showing the single multi-phase traffic signal<br />((coord|43|35|36.5|N|116|23|37.4|W))]]
A single-point urban interchange (SPUI) or single-point diamond interchange (SPDI) is a modification of a diamond interchange in which all four ramps to and from a controlled-access highway converge at a single, three-phase traffic light in the middle of an overpass or underpass. While the compact design is safer, more efficient, and offers increased capacity—with three light phases as opposed to four in a traditional diamond, and two left turn queues on the arterial road instead of four—the significantly wider overpass or underpass structure makes them more costly than most service interchanges.<ref>((cite web | title = Innovative Intersections and Interchanges | website = Virginia Department of Transportation | date = November 17, 2020 | url = https://www.virginiadot.org/info/innovative_intersections_and_interchanges/spui.asp | access-date = July 27, 2021))</ref><ref>((cite web | title = Single-Point Urban Interchanges | website = Missouri Department of Transportation | url = https://www.modot.org/single-point-urban-interchanges | access-date = July 27, 2021))</ref>
Since single-point urban interchanges can exist in rural areas, such as the interchange of [[U.S. Route 23]] with [[M-59 (Michigan highway)|M-59]] in [[Michigan]]; the term ''single-point diamond interchange'' is considered the correct phrasing.<ref>((cite book | title = A Policy on Geometric Design of Highways and Streets | author = Task Force on Geometric Design, 2000 | publisher = [[American Association of State Highway and Transportation Officials|AASHTO]] | chapter = 10.9.3.4: Single-Point Diamond Interchanges | year = 2001 | page = 10-48<!-- page numbers are based on chapters, this is page 48 of chapter 10. Page 910 in PDF --> | url = https://www.bestmaterials.com/PDF_Files/geometric_design_highways_and_streets_aashto.pdf | access-date = July 27, 2021 | isbn = 1-56051-156-7))</ref>

Single-point interchanges were first built in the early 1970s along [[U.S. Route 19]] in the [[Tampa Bay area]] of [[Florida]], including the [[Florida State Road 694|SR 694]] interchange in [[St. Petersburg, Florida|St. Petersburg]] and [[Florida State Road 60|SR 60]] in [[Clearwater, Florida|Clearwater]].<ref>((cite book |type = Report | first1 = James A. | last1 = Bonneson | first2 = Carroll J. | last2 = Messer | title = National Survey of Single-Point Urban Interchanges |id = FHWA/TX-88/1148-1 | publisher = Federal Highway Administration | date = March 1989 | url = https://static.tti.tamu.edu/tti.tamu.edu/documents/1148-1.pdf | access-date = July 27, 2021))</ref>

== See also ==
*[[Free-flow interchange]]
*[[Grade separation]]
*[[Intersection (road)]]
*[[Junction (traffic)]]
*[[Unused highway]]
*[[Ramp meter]]
*[[Roundabout]]

==Notes==
((notelist))

== References ==
((reflist))

== External links ==
((Commons category|Interchanges))
*[https://web.archive.org/web/20100527173652/http://www.tfhrc.gov/humanfac/01103/glossary.htm Glossary]((Snd)) Part of the publication [https://web.archive.org/web/20100527104450/http://www.tfhrc.gov/humanfac/01103/coverfront.htm ''Highway Design Handbook for Older Drivers and Pedestrians''] by the Turner-Fairbank Highway Research Center branch of the U.S. [[Federal Highway Administration]]
*[http://www.kurumi.com/roads/interchanges/ Kurumi.com U.S. interchanges directory]
*[https://web.archive.org/web/20050305150510/http://members.a1.net/wabweb/frames/kreuzf.htm Detailed history of interchanges with diagrams] ((in lang|de))
*[https://www.nj.com/insidejersey/2009/11/the_first_cloverleaf_interchan.html How New Jersey Saved Civilization: The first cloverleaf interchange]

((Road junction types))

((Authority control))

[[Category:Bridges]]
[[Category:Road interchanges| ]]
[[Category:Road infrastructure]]
[[Category:Road junction types]]

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Template:Road types (edit)
Template:SDcat (view source) (protected)
Template:Separated entries (view source) (template editor protected)
Template:Short description (view source) (protected)
Template:Short description/lowercasecheck (view source) (protected)
Template:Side box (view source) (template editor protected)
Template:Sister project (view source) (template editor protected)
Template:Snd (view source) (template editor protected)
Template:Spaced en dash (view source) (template editor protected)
Template:Spaces (view source) (protected)
Template:Unreferenced (view source) (template editor protected)
Template:Unreferenced section (view source) (template editor protected)
Template:Unsourced section (view source) (semi-protected)
Template:\ (view source) (template editor protected)
Module:Anchor (view source) (template editor protected)
Module:Arguments (view source) (protected)
Module:Authority control (view source) (template editor protected)
Module:Authority control/config (view source) (template editor protected)
Module:Category handler (view source) (protected)
Module:Category handler/blacklist (view source) (protected)
Module:Category handler/config (view source) (protected)
Module:Category handler/data (view source) (protected)
Module:Category handler/shared (view source) (protected)
Module:Check for unknown parameters (view source) (protected)
Module:Citation/CS1 (view source) (protected)
Module:Citation/CS1/COinS (view source) (protected)
Module:Citation/CS1/Configuration (view source) (protected)
Module:Citation/CS1/Date validation (view source) (protected)
Module:Citation/CS1/Identifiers (view source) (protected)
Module:Citation/CS1/Utilities (view source) (protected)
Module:Citation/CS1/Whitelist (view source) (protected)
Module:Citation/CS1/styles.css (view source) (protected)
Module:Coordinates (view source) (protected)
Module:Coordinates/styles.css (view source) (protected)
Module:Delink (view source) (protected)
Module:Disambiguation/templates (view source) (protected)
Module:EditAtWikidata (view source) (protected)
Module:Format link (view source) (template editor protected)
Module:Hatnote (view source) (template editor protected)
Module:Hatnote/styles.css (view source) (template editor protected)
Module:Hatnote list (view source) (template editor protected)
Module:In lang (view source) (template editor protected)
Module:Labelled list hatnote (view source) (template editor protected)
Module:Lang (view source) (template editor protected)
Module:Lang/ISO 639 synonyms (view source) (template editor protected)
Module:Lang/data (view source) (template editor protected)
Module:Language/data/iana languages (view source)
Module:Language/data/iana regions (view source)
Module:Language/data/iana scripts (view source)
Module:Language/data/iana suppressed scripts (view source)
Module:Language/data/iana variants (view source)
Module:Math (view source) (protected)
Module:Message box (view source) (protected)
Module:Message box/ambox.css (view source) (protected)
Module:Message box/configuration (view source) (protected)
Module:Multiple image (view source) (template editor protected)
Module:Namespace detect/config (view source) (protected)
Module:Namespace detect/data (view source) (protected)
Module:Navbar (view source) (protected)
Module:Navbar/configuration (view source) (protected)
Module:Navbar/styles.css (view source) (protected)
Module:Navbox (view source) (template editor protected)
Module:Navbox/configuration (view source) (template editor protected)
Module:Navbox/styles.css (view source) (template editor protected)
Module:Pagetype (view source) (protected)
Module:Pagetype/config (view source) (protected)
Module:Pagetype/disambiguation (view source) (protected)
Module:Pagetype/rfd (view source) (template editor protected)
Module:Pagetype/setindex (view source) (protected)
Module:Pagetype/softredirect (view source) (protected)
Module:Redirect hatnote (view source) (template editor protected)
Module:SDcat (view source) (protected)
Module:Separated entries (view source) (protected)
Module:Side box (view source) (template editor protected)
Module:Side box/styles.css (view source) (template editor protected)
Module:String (view source) (protected)
Module:TableTools (view source) (protected)
Module:Unicode data (view source) (template editor protected)
Module:Unsubst (view source) (protected)
Module:WikidataIB (view source) (template editor protected)
Module:WikidataIB/nolinks (view source) (template editor protected)
Module:WikidataIB/titleformats (view source) (template editor protected)
Module:Wikitext Parsing (view source) (protected)
Module:Yesno (view source) (protected)

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Retrieved from "https://en.wikipedia.org/wiki/Interchange_(road)"