State Road 75
SR 75 highlighted in red
Route information
Maintained by INDOT
Length	59.563 mi[1] (95.857 km)
Southern segment
Length	36.896 mi[1] (59.378 km)
South end	US 40
Major intersections	US 136 in Jamestown I-74
North end	SR 47 in Thorntown
Northern segment
Length	22.667 mi[1] (36.479 km)
South end	US 421 / SR 38 / SR 39 near Frankfort
Major intersections	SR 26 near Sedalia SR 18 in Flora
North end	SR 218 in Camden
Location
Country	United States
State	Indiana
Counties	Boone, Hendricks, Putnam, Carroll, Clinton
Highway system
Indiana State Highway System Interstate US State Scenic
← I-74 → I-80

State Road 75, the highest two-digit route in the U.S. state of Indiana consists of two discontinuous north–south segments.

Route description

Southern section

The southern section is about 37 miles (60 km) long. It begins at U.S. Route 40 at the Putnam-Hendricks county line and runs northward through the towns of Coatesville and North Salem in Hendricks County, and Jamestown and Advance in Boone County. There is a junction with U.S. Route 136 at Jamestown, and a junction with Interstate 74 just to the north. The northern terminus is at State Road 47 in the town of Thorntown.

Northern section

The northern section is 22.7 miles (36.5 km) long. It begins at U.S. Route 421 / State Road 38 / State Road 39 in Frankfort in Clinton County and runs northward, crossing State Road 26 east of Rossville, and passing through the town of Flora where it crosses State Road 18. The northern terminus is at State Road 218 in the town of Camden in Carroll County.

In August 2008, the Indiana Department of Transportation awarded Carroll County a grant of $1.2 million to be used to extend the road 3 miles (4.8 km) north, to connect with the planned relocation of State Road 25.^{[citation needed]}

Former route in Spencer County

When the Glover H. Cary Bridge between Owensboro, Kentucky and Rockport, Indiana opened in September 1940, its northern end connected to a new nine-mile (14 km) stretch of state highway through Spencer County that fed traffic to State Road 66. As the Kentucky highway which connected to the bridge was designated Kentucky 75, Indiana gave its connector road the same number.

In 1954, U.S. Route 231 was extended through Indiana, and the southernmost stretch of the new U.S. route in Indiana was routed along S.R. 75. The road was signed with both designations. The Indiana Department of Highways removed 75's designation from U.S. 231 in Spencer County by 1979, along with 231's other concurrent routes throughout the state (others included S.R. 45 and S.R. 43).

In October 2002, with the opening of the William H. Natcher Bridge and the relocation of U.S. 231, this segment of highway was again redesignated, this time as a southern extension of S.R. 161.

Major intersections

County	Location	mi[1]	km	Destinations	Notes
Putnam	Jefferson Township	0.000	0.000	US 40 – Brazil, Indianapolis	Southern terminus of SR 75
		0.177	0.285	SR 240 – Greencastle
Hendricks	Marion Township	9.478	15.253	US 36 – Rockville, Danville
	North Salem	17.057	27.451	SR 236 – Danville
Hendricks–Boone county line	Jamestown	21.787	35.063	SR 234 west – Ladoga	Western end of SR 234 concurrency
Boone		22.233	35.781	US 136 / SR 234 – Brownsburg, Crawfordsville	Eastern end of SR 234 concurrency and terminus of SR 234
		23.558– 23.687	37.913– 38.121	I-74 – Indianapolis, Danville	Exit number 52 on I-74
	Jefferson Township	31.365	50.477	SR 32 – Crawfordsville, Lebanon
	Thorntown	36.896	59.378	SR 47 – Crawfordsville	Northern terminus of the southern section of SR 75
Gap in route
Clinton	Frankfort	36.897	59.380	US 421 / SR 38 / SR 39 – Delphi, Indianapolis	Southern terminus of the northern section of SR 75
	Owen Township	46.149	74.270	SR 26 – Lafayette, Kokomo
Carroll	Flora	55.183	88.808	SR 18 – Delphi, Marion
	Camden	59.563	95.857	SR 218	Northern terminus of SR 75
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus