Interstate Highways of the State Trunkline Highway System

Highway markers in different years for Interstate 69 (1957), Business Loop Interstate 75 (1957), Interstate 94 (1971), Business Spur Interstate 96 (1971) and the Capitol Loop (1989)
Michigan's Interstates highlighted in red
System information
Maintained by MDOT and MBA
Length1,238.709 mi[2] (1,993.509 km)
Plus 197.816 mi [2] (318.354 km) of business routes
FormedJune 29, 1956 (1956-06-29)[1]
Highway names
InterstatesInterstate nn (I‑nn)
Business Loops:Business Loop Interstate nn (BL I‑nn)
Business Spurs:Business Spur Interstate nn (BS I‑nn)
System links

The Interstate Highways in Michigan are the segments of the national Dwight D. Eisenhower System of Interstate and Defense Highways[3] that are owned and maintained by the U.S. state of Michigan,[4] totaling about 1,239 miles (1,994 km).[2] The longest of these, Interstate 75 (I-75), is also the longest highway of any kind in the state.[5] On a national level, the standards and numbering for the system are handled by the Federal Highway Administration (FHWA) and the American Association of State Highway and Transportation Officials (AASHTO), while the highways in Michigan are maintained by the Michigan Department of Transportation (MDOT) and the Mackinac Bridge Authority (MBA). The Interstates in Michigan have their origins in World War II-era expressways built in the Detroit area. After the system was created in 1956, the state highway department completed its first border-to-border Interstate in 1960. The last highway was completed in 1992, giving Michigan a total of 13 Interstate freeways. The original allotment of mileage to Michigan which would receive federal funding was expanded in 1968, and the United States Congress designated an additional highway in the 1990s that has not yet been built.

There are also 26 current business routes that connect cities bypassed by the Interstates; 23 are business loops that connect on both ends to their parent highway, and three are business spurs that connect on only one end. I-496 has the Capitol Loop as its connection to the Michigan State Capitol in downtown Lansing. Another six business routes have been designated but are either no longer signed or maintained as state highways.


MDOT is the agency responsible for the day-to-day maintenance and operations of the State Trunkline Highway System, which includes the Interstate Highways in Michigan. These highways are built to Interstate Highway standards,[6] meaning they are all freeways with minimum requirements for full control of access, design speeds of 50 to 70 miles per hour (80 to 113 km/h) depending on type of terrain, a minimum of two travel lanes in each direction, and specific widths of lanes or shoulders;[7] exceptions from these standards have to be approved by the FHWA.[8] The numbering scheme used to designate the Interstates was developed by AASHTO, an organization composed of the various state departments of transportation in the United States.[9]

The Interstate Highway System covers about 1,240 miles (2,000 km) in the state and consists of four primary highways and nine auxiliary highways. There are additional 29 business routes associated with the system in Michigan. The longest segment of Interstate Highway in the state is Interstate 75 (I-75) at just under 396 miles (637 km); the shortest is I-375 at 1.1 miles (1.8 km). The length of I-75, the longest highway of any kind in the state,[5] includes the Mackinac Bridge, which is maintained by the MBA, the only section of state highway not under MDOT jurisdiction.[a] The Mackinac Bridge is one of three monumental bridges in the state used by I-75; the others are the Zilwaukee and International bridges. A fourth, the privately owned Ambassador Bridge connects I-75 and I-96 in Detroit to Canada.[11]


Construction of the first expressways in Michigan predates the Interstate Highway System. During World War II, the Michigan State Highway Department (MSHD)[b] built the Willow Run and Detroit Industrial expressways (now part of I-94) to carry workers from Detroit to the defense plants at Willow Run Airport.[14] The state created the Michigan Turnpike Authority (MTA) in 1951,[15] which proposed the construction of a toll freeway to run north–south in the state. The original termini for the Michigan Turnpike were Bridgeport and Rockwood.[16] Interagency politics stalled progress on any proposed turnpikes[17] while MSHD had three freeways under planning or construction.[18]

1958 planning map for Michigan's Interstate Highways
1958 planning map for Michigan's Interstate Highways

The Interstate Highway System was authorized by the Federal Aid Highway Act of 1956,[1] and the state had already designed several freeways for its portion of that system. Seizing the opportunity brought by a 1957 state law, the department sold $700 million in bonds (equivalent to $4.97 billion in 2011[19]) in the late 1950s and early 1960s to finance land purchases and construction of the new freeways. The goal was to connect every city with a population over 50,000 with four-lane freeways that could accommodate rural traffic traveling at 70 mph (110 km/h).[18] The MSHD delayed numbering these freeways as part of the Interstate Highway System until the federal government had finalized the designations to be assigned to Michigan's freeways.[20] The first highway to be signed as an Interstate in Michigan was I-75, which received signage in late 1959, along a section near the Ohio state line that opened to traffic in October 1957.[21][22] I-94 was the first of the Interstates to be completed border to border in a US state.[23] In 1974, the state implemented mileage-based exit numbers along the Interstates in Michigan.[24]

The MSHD asked for 600 miles (970 km) in additions to the state's Interstate mileage in 1968. Included in these requests were the extension of the Davison Freeway (now M-8), the extension of I-69 from Marshall to Port Huron, and the conversion of the northern sections of US Highway 23 (US 23) and US 131.[25] Of these, the I-69 proposal was approved when the United States Congress extended it to terminate in at I-75 in Flint. The highway was lengthened twice more: to I-475 in 1973 and to Port Huron on February 10, 1987.[26] These last two extensions were classified non-chargeable mileage, or segments not financed through the Interstate Highway fund.[27] The federal government paid 90 percent of the cost of the chargeable mileage originally approved.[18]

The last of Michigan's Interstates to be completed was I-69, the last segment of which opened in 1992.[28] Since then, the United States Congress has designated an additional primary Interstate, I-73 in the state. All studies by MDOT on that highway were cancelled in 2001 over funding concerns.[29] Press reports state there is a "lack of need" for the freeway in the state,[30] and the department has no plans to revive I-73 as of 2011.[31] If built as designated, I-73 would cross into Michigan near Toledo, Ohio, and connect Jackson, Lansing, and Clare to I-75 at Grayling.[32]

Primary Interstates

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
I-69 202.317 325.598 I-69 at Kinderhook Township Hwy. 402 at Port Huron 01967-10-111967[33] current Last Interstate completed in Michigan when finished in 1992;[28] segments named the Chevrolet (or Chevrolet-Buick) Freeway, or the Pearl Harbor or Purple Heart highways[34]
I-75 395.916 637.165 I-75 at Erie Township International Bridge at Sault Ste. Marie 01959-10-011959[21] current I-75 is the longest highway of any kind in Michigan[5] and the only highway on both of the Upper & Lower peninsulas. It is the only freeway in the Upper Peninsula and was completed in 1973.[35] Segments are named the Detroit–Toledo,[22] Fisher, Chrysler, American Legion, Prentiss M. Brown and G. Mennon Williams freeways[36]
I-94 275.398 443.210 I-94 at New Buffalo Township Hwy. 402 at Port Huron 01959-11-011959[20] current First Interstate Highway completed between state borders in 1960;[23] sections named the Detroit Industrial or Edsel Ford freeways[37]
I-96 192.032 309.046 US 31 & Bus. US 31 in Norton Shores I-75 in Detroit 01959-11-011959[20] current One section previously known as the Brighton–Farmington Freeway,[12] other sections named the Jeffries[38] and Rosa Parks freeways;[39] completed in 1977[12]

Auxiliary Interstates

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
I-194 3.374 5.430 I-94 and M-66 in Battle Creek M-66 in Battle Creek 01961-01-011961[40] current Called the Sojourner Truth Downtown Parkway,[41] or The Penetrator,[42][c] I-194 serves as a spur into downtown Battle Creek and was completed in 1966.[44]
I-196 30.073 48.398 US 31 and BS I-196/Bus. US 31 in Norton Shores I-96 in Grand Rapids 01959-01-011959[20] 01963-01-011963[45] Now the western end of I-96, I-196 was a spur from Grand Rapids to Muskegon completed in 1962.[46]
I-196 80.629 129.760 I-94/US 31 in Benton Township near Benton Harbor I-96/M-37 in Grand Rapids 01963-01-011963[45] current The Gerald R. Ford Freeway[47] was completed in 1974[48] as a connector from Grand Rapids to I-94 in the Benton HarborSt. Joseph area.
I-275 35.026 56.369 I-75 in Frenchtown Township near Newport I-96, I-696 and M-5 in Novi 01974-01-011974[49] current Completed in 1977[50] as a partial western bypass of Detroit.
I-296 3.189 5.132 I-196 and US 131 in Grand Rapids I-96 in Walker 01962-12-171962[51] current Michigan was granted approval to remove signage referring to I-296 on December 3, 1979.[52] The freeway is signed as US 131 and connects I-96 and I-196 near downtown Grand Rapids.
I-375 1.147 1.846 BS I-375 in Detroit I-75 in Detroit 01964-06-121964[53] current I-375 is the southern end of the Walter P. Chrysler Freeway,[54] and as of 2007 it was the shortest signed Interstate in the country,[53] but I-110 in Texas has been signed since then.[55] I-375 is a spur connecting the Detroit Riverfront area to I-75.
I-475 16.866 27.143 I-75 in Grand Blanc Township I-75/US 23 in Mount Morris Township 01973-01-011973[56] current Called the David Dunbar Buick Freeway,[56] or the UAW Freeway,[57] I-475 is a loop into Downtown Flint completed in 1981.[58]
I-496 11.481 18.477 I-96/I-69 in Delta Township I-96 and US 127 in Delhi Township 01963-01-011963[59] current I-496 is the R. E. Olds Freeway,[60] a loop into Downtown Lansing completed in 1970[61]
I-675 7.929 12.760 I-75/US 23 in Buena Vista Township I-75/US 23 in Zilwaukee Township 01971-01-011971[62] current I-675 is a loop into downtown Saginaw.
I-696 28.368 45.654 I-96/I-275 and M-5 in Novi I-94 in St. Clair Shores 01963-01-011963[63] current Walter P. Reuther Freeway;[64] completed in 1989[65]
  •       Former

Proposed Interstates

Number Southern or western terminus Northern or eastern terminus Notes
I-67 South Bend, IN Kalamazoo Proposed designation in 1957 for what was shifted to become I-69[66][67]
Benton Harbor Grand Rapids Later proposed in 1958 and 1963 for what became I-196[46][67]
I-73 Newport Novi Proposed in 1958 for what became I-275[67]
Ottawa Lake Grayling[d] Designated by Congress in 1991 and 1995, but all future study halted by MDOT; essentially removed from consideration[29][32][68]
I-77 Erie Port Huron Proposed designation in 1957 for what became I-94 from Detroit to Port Huron and cosigned with I-75 from Detroit to state line[66]
I-92 Benton Harbor Detroit Proposed designation in 1957 for what became I-94 from Detroit to Benton Harbor[66]
I-94N Muskegon Grand Rapids Proposed designation in 1957 for what became I-196, and now I-96 from Grand Rapids to Muskegon[66]
I-98 Novi St. Clair Shores Proposed designation in 1958 for what became I-696[67]

Business routes

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
BL I-69 5.202 8.372 I-69 on the OvidColdwater township line I-69 in Coldwater 01967-01-011967[33] current
BL I-69 4.891 7.871 I-69 on the CarmelEaton township line I-69 in Charlotte 01974-01-011974[69] current
BL I-69 14.668 23.606 I-96/I-69 and M-43 in Delta Township I-69 in Bath Township 01987-01-011987[70] current Longest business route in the state, serves Lansing and East Lansing[2]
BL I-69 5.408 8.703 I-94/I-69 in Port Huron Township I-94/I-69 in Port Huron 01984-01-011984[71] current
BL I-75 8.384 13.493 I-75 in Bloomfield Township I-75 in Auburn Hills 01963-01-011963[72] current Follows Woodward Avenue through downtown Pontiac[2]
BL I-75 7.338 11.809 I-75/US 10/US 23 in Buena Vista Township I-75/US 10/US 23 in Zilwaukee Township 01961-01-011961[73] 01971-01-011971[74] Previously served downtown Saginaw[74]
BS I-75 3.047 4.904 I-75/US 23 and US 10 in Monitor Township M-25 in Bay City 01961-01-011961[73] current Previously part of a business loop[74]
BL I-75 5.525 8.892 I-75 in Horton Township I-75/M-55 in Ogemaw Township 01973-01-011973[75] current Replaced Bus. M-76 through West Branch[75]
BL I-75 6.935 11.161 I-75 and M-18 in Higgins Township I-75 on the GerrishBeaver Creek township line 01973-01-011973[75] current Serves Roscommon[2]
BL I-75 5.823 9.371 I-75 in Grayling Township I-75 and M-93 in Grayling Township 01961-01-011961[73] current Serves Grayling[2]
BL I-75 3.391 5.457 I-75 in Bagley Township I-75 and M-32 in Gaylord 01986-01-011986[76] current
BL I-75 3.975 6.397 I-75 and M-68 in Tuscarora Township I-75 and M-27 in Tuscarora Township proposed[77] Would serve Indian River if designated
BL I-75 4.719 7.594 I-75 and US 2 in St. Ignace I-75 and H-63 in Evergreen Shores 01960-01-01c. 1960[78] current
BS I-75 5.867 9.442 I-75 in Sault Ste. Marie Portage Avenue in Sault Ste. Marie 01962-01-011962[79] current
BL I-94 10.705 17.228 I-94 in Lincoln Township I-94/US 31 in Benton Township 01960-11-021960[80] current Serves Benton Harbor and St. Joseph[2]
BS I-94 2.885 4.643 M-96 in Kalamazoo I-94 in Comstock Township 01962-01-011962[81] current Previously a full business loop, truncated in 2019 after Kalamazoo accepted jurisdiction of much of the routing;[82] some portions retained as unsigned highway[83]
BL I-94 14.052 22.615 I-94 in Battle Creek I-94 and M-96 in Emmett Township 01962-01-011962[81] current
BL I-94 5.707 9.185 I-94 and I-69 in Marshall Township I-94 in Marengo Township 01962-01-011962[81] current Serves Marshall[2]
BL I-94 4.520 7.274 I-94 in Sheridan Township I-94 in Parma Township 01962-01-011962[81] current Serves Albion[2]
BL I-94 10.274 16.534 I-94 in Blackman Township I-94 in Leoni Township 01962-01-011962[81] current Serves Jackson[2]
BL I-94 8.436 13.576 I-94 in Ann Arbor I-94 and US 23 in Pittsfield Township 01962-01-011962[81] current
BL I-94 8.536 13.737 I-94 in Kimball Township I-94/I-69 in Port Huron 01986-01-011986[84] current
BS I-96 6.160 9.914 Carferry docks in Muskegon I-96, US 31 and Bus. US 31 in Norton Shores 01963-10-211963[85] 01984-01-011984[86] Replaced BS I-196
BS I-96 1.292 2.079 Grand River Avenue in Portland I-96 in Portland 01978-09-181978[87] 02007-10-312007[88]
BL I-96 13.545 21.799 I-96 in Watertown Township I-96 in Lansing 01962-01-011962[89] current
BL I-96 5.415 8.715 I-96 in Howell Township I-96 in Genoa Township 01962-01-011962[90] current Serves Howell[2]
BL I-96 4.365 7.025 M-5 in Farmington Hills M-5 in Farmington Hills 01962-01-011962[90] current Now an unsigned highway along Grand River Avenue serving Farmington[91]
BS I-96 7.033 11.319 I-96 and M-5 in Detroit Cass and Grand River avenues in Detroit 01962-01-011962[90] 02016-05-012016 Was last an unsigned trunkline along Grand River Avenue in Detroit[91]
BS I-196 6.160 9.914 Carferry docks in Muskegon I-196, US 31 and Bus. US 31 in Norton Shores 01962-12-121962[92] 01963-10-211963[85] Replaced by BS I-96
BL I-196 3.572 5.749 I-196/US 31 and M-140 in South Haven Township I-196/US 31 in South Haven 01963-01-011963[93] current
BL I-196 11.508 18.520 I-196/US 31 in Laketown Township I-196 in Zeeland Township 01974-01-011974[94] current Serves Holland[2]
BS I-196 2.433 3.916 I-196 in Wyoming Granville Avenue & Clyde Park Avenue on the Wyoming–Grand Rapids city line 01974-01-011974[95] current Previously extended into Grand Rapids and terminated at US 131 before December 2017[96]
BS I-375 0.167 0.269 M-3 and M-10 in Detroit I-375 in Detroit 01963-01-011963[53] current Unsigned along Jefferson Avenue[e]
Capitol Loop 2.381 3.832 I-496 and M-99 in Lansing I-496 and BL I-96 in Lansing 01989-01-011989[99] current Also designated Connector 496[100] or Capitol Loop I-496 by MDOT[101]
BS I-696 18.562 29.873 I-696 and US 24 in Southfield Jefferson Avenue in Detroit 01961-01-01c. 1961[90] 01970-01-011970[102] Previous designation for the John C. Lodge Freeway, now M-10[102][103]
  •       Former

See also


  1. ^ The Mackinac Bridge Authority (MBA) is an independent state agency responsible for the Mackinac Bridge and thus maintains that section of the overall highway system. The MBA works with MDOT but does not report to it. The executive secretary of the MBA is appointed by MDOT with MBA approval.[10]
  2. ^ The Michigan State Highway Department was reorganized into the Michigan Department of State Highways and Transportation on August 23, 1973,[12] and the name was later shortened to its current form in 1978.[13]
  3. ^ When the MSHD was planning the freeway network in the state, they called all of the auxiliary Interstate Highways, "Penetrator"[43]
  4. ^ The legislation defining the I-73 corridor specifies Sault Ste. Marie and Detroit as the northern termini, but the Grayling–Sault Ste. Marie or Toledo–Detroit segments overlap I-75 with no requirement to overlap the highway designations. Similarly, Congress included I-94 between Chicago and Port Huron in the I-69 corridor to make it eligible for funding.[32]
  5. ^ The section of Jefferson Avenue that connects I-375 with M-10 is combined with the freeway as I-375 on MDOT right-of-way (ROW) maps that document property transfers and ROW descriptions,[97] but in the department's Physical Reference Finder Application, the street is marked as BS I-375,[2] a designation missing from the official state map for the public.[98]



  1. ^ a b McNichol (2006), p. 106.
  2. ^ a b c d e f g h i j k l m n o p q Michigan Department of Transportation & Michigan Center for Shared Solutions and Technology Partnerships (2009). MDOT Physical Reference Finder Application (Map). Michigan Department of Transportation. Retrieved November 17, 2010.
  3. ^ Swift (2011), p. 5.
  4. ^ Hamilton (2007), p. 8.
  5. ^ a b c Michigan Department of Transportation (July 7, 2015). "Road & Highway Facts". Michigan Department of Transportation. Retrieved August 21, 2015.
  6. ^ Lewis (2013), p. 253.
  7. ^ McNichol (2006), pp. 10–11.
  8. ^ Zander, Mark, ed. (September 19, 2013). "Chapter 11: Design, Section 44: Interstate Highways" (PDF). Facilities Development Manual. Madison: Wisconsin Department of Transportation. p. 2. OCLC 893873063. Archived from the original (PDF) on April 16, 2014. Retrieved April 14, 2014.
  9. ^ McNichol (2006), pp. 57, 121.
  10. ^ "Bridge Legislation Signed". The Grand Rapids Press. Associated Press. December 29, 2005. p. B3. OCLC 9975013.
  11. ^ Hyde (1993), pp. 147–168.
  12. ^ a b c Kulsea & Shawver (1980), p. 27.
  13. ^ Kulsea & Shawver (1980), pp. 30–31.
  14. ^ Kulsea & Shawver (1980), pp. 17–18.
  15. ^ MDOT (2010), p. 12.
  16. ^ "Michigan To Push Its North–South Turnpike: Toll Road To Link Centers of Industrial Areas". Youngstown Vindicator. February 21, 1955. p. 2. OCLC 5424159. Retrieved October 30, 2012 – via Google News.
  17. ^ Bagley, Les (October 25, 2007). "Autos Across Mackinac: Michigan Decides Against Building Turnpikes". The St. Ignace News. OCLC 36250796. Archived from the original on April 17, 2013. Retrieved October 30, 2012.
  18. ^ a b c Kulsea & Shawver (1980), p. 19.
  19. ^ Thomas, Ryland & Williamson, Samuel H. (2020). "What Was the U.S. GDP Then?". MeasuringWorth. Retrieved September 22, 2020. United States Gross Domestic Product deflator figures follow the Measuring Worth series.
  20. ^ a b c d "Michigan Delays Road Number System". Toledo Blade. June 4, 1959. p. 11. OCLC 12962635. Retrieved November 21, 2010 – via Google News.
  21. ^ a b "Interstate 75 Road Markers Are Unveiled". The Herald-Press. St. Joseph, MI. Associated Press. October 13, 1959. p. 3. OCLC 10117184. Retrieved July 10, 2018 – via
  22. ^ a b "Ohio, Michigan Dedicate New Expressway". Chicago Daily Tribune. May 23, 1959. p. 3. OCLC 1554151. Retrieved July 10, 2018 – via
  23. ^ a b "Michigan Became Leading Highway Builder in 1960". The Holland Evening Sentinel. United Press International. December 29, 1960. p. 12. OCLC 13440201. Retrieved August 11, 2018 – via
  24. ^ "Interstates Get New Exit Signs: Michigan Using National System". The Blade. Toledo, OH. Associated Press. July 4, 1974. p. 19. OCLC 12962717.
  25. ^ "Highway Additions Requested By State". The Owosso Argus-Press. Associated Press. November 14, 1968. p. 7. OCLC 9802802. Retrieved December 5, 2010 – via Google News.
  26. ^ Weingroff, Richard (July 16, 2013) [1998]. "Part I: History". The Dwight D. Eisenhower System of Interstate and Defense Highways. Federal Highway Administration. Retrieved August 18, 2013.
  27. ^ Weingroff, Richard (July 16, 2013) [1998]. "Part II: Mileage". The Dwight D. Eisenhower System of Interstate and Defense Highways. Federal Highway Administration. Retrieved August 18, 2013.
  28. ^ a b "I-69 Now Open South of Lansing". Marshall Evening Chronicle. Associated Press. October 17, 1992. p. 20. OCLC 18110507. Retrieved August 11, 2018 – via
  29. ^ a b Debnar, Kari (June 12, 2001). "MDOT Postpones Further Studies Along I-73 Corridor" (Press release). Michigan Department of Transportation. Archived from the original on February 28, 2005. Retrieved September 28, 2010.
  30. ^ Hickey, JoAnne (August 22, 2007). "South Takes the Lead: I-73 Will Push from South to North" (PDF). Marion Star & Mullins Enterprise. Marion, SC. p. 5A. OCLC 761993706. Archived from the original (PDF) on May 8, 2012. Retrieved January 4, 2011.
  31. ^ Pelham, Dennis (July 16, 2011). "Group Seeks to Revive I-73 Interest in Michigan". The Daily Telegram. Adrian, MI. p. A8. OCLC 33972687. Archived from the original on May 8, 2012. Retrieved September 6, 2011.
  32. ^ a b c United States Congress (November 28, 1995). "National Highway System Designation Act of 1995". Washington, DC: Government Printing Office. § 1105(c)(5). Pub.L. 104–59 (text) (pdf). Retrieved September 28, 2010 – via Federal Highway Administration.
  33. ^ a b "Indiana, Mich., To Open Road". The News-Palladium. Benton Harbor, MI. Associated Press. September 29, 1967. p. 12. OCLC 10117334. Retrieved July 11, 2018 – via
  34. ^ Barnett (2004), pp. 40–41, 49–50, 171–172, 179–180.
  35. ^ "Around the State: West Branch". Traverse City Record-Eagle. United Press International. November 2, 1973. p. 3. OCLC 30098364. Retrieved July 10, 2018 – via
  36. ^ Barnett (2004), pp. 22–23, 81–82, 88, 177–178, 233.
  37. ^ Barnett (2004), pp. 67–68, 81.
  38. ^ Barnett (2004), pp. 120–121.
  39. ^ Michigan Legislature (2001). "Rosa Parks Memorial Highway". Michigan Memorial Highway Act (Excerpt) Act 142 of 2001. State of Michigan. MCL 250.1098. Retrieved August 18, 2006.
  40. ^ MSHD (1960), Battle Creek inset; MSHD (1961), Battle Creek inset.
  41. ^ Barnett (2004), p. 201.
  42. ^ Vander Meer, John J. (March 18, 2002). "Penetrator to Get $1.6M Face-Lift". Battle Creek Enquirer. pp. 1A, 7A. OCLC 33956507. Retrieved July 12, 2018 – via
  43. ^ Richard, Tim (April 3, 1986). "I-275: The Interstate that Isn't". Observer. Livonia, MI. OCLC 22646576.
  44. ^ MDSH (1966), Battle Creek inset; MDSH (1967), Battle Creek inset.
  45. ^ a b "New Numbers Seen for Road". The Holland Evening Sentinel. United Press International. October 23, 1963. p. 4. ISSN 1050-4044. OCLC 13440201. Retrieved April 12, 2016 – via
  46. ^ a b "Would Shift Route Number: Mackie Seeks Int. 96 Designation for Grand Rapids–Muskegon Stretch". The Grand Rapids Press. May 1, 1963. p. 32. OCLC 9975013.
  47. ^ Barnett (2004), p. 89.
  48. ^ "Ford Will Miss I-196 Dedication". The News-Palladium. Benton Harbor, MI. Associated Press. November 30, 1974. p. 10. OCLC 10117334. Retrieved July 12, 2018 – via
  49. ^ MDSHT (1974), §§ M13–N13; MDSHT (1975), §§ M13–N13.
  50. ^ "Freeway to Open Jan. 14". Ludington Daily News. January 8, 1977. p. 2. OCLC 427389796. Retrieved July 12, 2018 – via
  51. ^ "Driver's Boon: Int. 296 Opening Finishes City Freeway, Links Kalamazoo, Muskegon". The Grand Rapids Press. December 17, 1962. p. A1. OCLC 9975013.
  52. ^ Merchant, David A. (December 3, 1979). "Removal of I-296 Designation, Grand Rapids". Letter to John P. Woodford. Lansing, MI: Federal Highway Administration. Retrieved June 3, 2019 – via Wikisource.
  53. ^ a b c American Association of State Highway and Transportation Officials (2006). "Today in Interstate History: June 12, 1964". The Interstate is 50. American Association of State Highway and Transportation Officials. Archived from the original on August 4, 2007. Retrieved March 25, 2010.
  54. ^ Barnett (2004), p. 233.
  55. ^ Texas Department of Transportation (2010). I-110, US 54, I-10 and US 180 (Highway guide sign). El Paso, TX: Texas Department of Transportation. Retrieved April 11, 2014.
  56. ^ a b Barnett (2004), pp. 40–41.
  57. ^ Barnett (2004), p. 215.
  58. ^ MDOT (1981), § K12; MDOT (1982), § K12.
  59. ^ "New Highway Opened". Ironwood Daily Globe. Associated Press. December 21, 1963. p. 9. OCLC 10890811. Retrieved July 11, 2018 – via
  60. ^ Barnett (2004), p. 165.
  61. ^ Miller, Matthew (February 22, 2009). "Looking Back: I-496 Construction, A Complicated Legacy". Lansing State Journal. pp. 1A, 8A. ISSN 0274-9742. OCLC 6678181. Retrieved July 12, 2018 – via
  62. ^ MDSH (1971), § J12; MDSH (1972), § J12.
  63. ^ Brown, Warren (February 4, 1990). "Home of the American Auto Finds Reuther Freeway a Mixed Blessing". The Washington Post. p. H2. ISSN 0740-5421. OCLC 9965758. Retrieved July 13, 2012. (subscription required)
  64. ^ Barnett (2004), p. 234.
  65. ^ Leavitt, Paul (December 11, 1989). "Nationline". USA Today. p. 3A. ISSN 0734-7456. OCLC 8799626.
  66. ^ a b c d Public Roads Administration (August 14, 1957). Official Route Numbering for the National System of Interstate and Defense Highways, as Adopted by the American Association of State Highway Officials (Map). Scale not given. Washington, DC: Public Roads Administration. Retrieved November 22, 2010.
  67. ^ a b c d Michigan State Highway Department (April 25, 1958). Recommended Interstate Route Numbering for Michigan (Report). Lansing: Michigan State Highway Department. Archived from the original on August 5, 2004. Retrieved September 4, 2010.
  68. ^ United States Congress (December 18, 1991). "Intermodal Surface Transportation Efficiency Act of 1991". Washington, DC: Government Printing Office. § 1105(c)(5). Pub.L. 102–240. Retrieved September 28, 2010 – via Bureau of Transportation Statistics.
  69. ^ MDSHT (1974), § L10; MDSHT (1975), § L10.
  70. ^ MDOT (1987), § L11; MDOT (1988), § L11.
  71. ^ MDOT (1984), § K14; MDOT (1985), § K14.
  72. ^ MSHD (1963), § L13; MSHD (1964), § L13.
  73. ^ a b c MSHD (1961), §§ G10, J12; MSHD (1962), §§ G10, J12.
  74. ^ a b c MDSH (1971), Saginaw inset; MDSH (1972), Saginaw inset.
  75. ^ a b c MDSH (1973), §§ G10, H11; MDSHT (1974), §§ G10, H11.
  76. ^ MDOT (1986), § F10; MDOT (1987), § F10.
  77. ^ Hahn, Kortny (March 3, 2017). "Road Comm. Eyes I-75 Business Loop". Holland Sentinel. Retrieved March 10, 2017.
  78. ^ MSHD (1960), § D10; MSHD (1961), § D10.
  79. ^ MSHD (1962), § C10; MSHD (1963), § C10.
  80. ^ "Golden Belt Connectors Next in Line: Freeway Opens to Traffic". The News-Palladium. Benton Harbor, MI. November 3, 1960. p. 1. OCLC 10117334. Retrieved May 22, 2015 – via
  81. ^ a b c d e f "Area Road Signs To Be Changed". The News-Palladium. Benton Harbor, MI. Associated Press. January 9, 1962. § 2, p. 5. OCLC 10117334. Retrieved July 13, 2018 – via
  82. ^ Barrett, Malachi (January 8, 2019). "Kalamazoo Accepts Control of State Trunklines Spanning City". MLive. Booth Newspapers. Retrieved April 23, 2019.
  83. ^ Michigan Department of Transportation (2019). Truck Operator's Map (PDF) (Map). c. 1:221,760. Lansing: Michigan Department of Transportation. Kalamazoo inset.
  84. ^ MDOT (1986), § K14; MDOT (1987), §K14.
  85. ^ a b MSHD (1963), § K7; MSHD (1964), § K7.
  86. ^ MDOT (1984), Muskegon inset; MDOT (1985), Muskegon inset.
  87. ^ Michigan Department of Transportation & V3 Consultants (February 2003). "Ionia County" (PDF) (Map). Right-of-Way File Application. Scale not given. Lansing: Michigan Department of Transportation. Sheet 71. Retrieved December 29, 2013.
  88. ^ Michigan Department of Transportation (October 31, 2007). "Contract Number 103107". Michigan Department of Transportation. Retrieved November 2, 2007.
  89. ^ MSHD (1962), Lansing inset; MSHD (1963), Lansing inset.
  90. ^ a b c d MSHD (1962), Detroit Metropolitan Area inset; MSHD (1963), Detroit Metropolitan Area inset.
  91. ^ a b MDOT (2013), Detroit and Vicinity inset.
  92. ^ MSHD (1962), § K7; MSHD (1963), § K7.
  93. ^ MSHD (1963), §§ M7–L8; MSHD (1964), §§ M7–L8.
  94. ^ MDSHT (1974), § L8; MDSHT (1975), § L8.
  95. ^ MDSHT (1974), Grand Rapids inset; MDSHT (1975), Grand Rapids inset.
  96. ^ Biolchini, Amy (August 24, 2017). "Grand Rapids Will Have More Control Over 11 Streets in MDOT Deal". MLive. Booth Newspapers. Retrieved November 22, 2017.
  97. ^ Michigan Department of Transportation & Gosselin Group (February 11, 2010). "Wayne County" (PDF) (Map). Right-of-Way File Application. Scale not given. Lansing: Michigan Department of Transportation. Sheet 173. Retrieved April 11, 2014.
  98. ^ MDOT (2015), Downtown Detroit inset, § H13.
  99. ^ Michigan Department of Transportation (August 29, 2007). "Ingham County" (PDF) (Map). Right-of-Way File Application. Scale not given. Lansing: Michigan Department of Transportation. Sheet 180. Retrieved October 15, 2008.
  100. ^ Michigan Department of Information Technology (May 1, 2008). "Appendix C: State Trunkline Connector Routes" (PDF). Michigan Geographic Framework. Michigan Department of Information Technology. Archived (PDF) from the original on January 8, 2011. Retrieved October 15, 2008.
  101. ^ MDOT (2006), Lansing inset.
  102. ^ a b MDSH (1970), Detroit and Vicinity inset, §§ A6–E9; MDSH (1971), Detroit and Vicinity inset, §§ A6–E9.
  103. ^ Barnett (2004), pp. 121–122.

Works cited

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