Indiana Road Network

By | October 13, 2022

Indiana is an important transit state, especially for east-west traffic. Several major Interstate Highways run through the state, many of which converge in Indianapolis. Indianapolis is also known as the ‘Crossroads of America’.

Road management

The state highway authority is the Indiana Department of Transportation, abbreviated INDOT. INDOT manages approximately 17,700 kilometers of road and nearly 6,000 bridges. INDOT has its origins in the Indiana State Highway Commission that was established in 1919. This later became the Indiana Department of Highways, and was merged into the Indiana Department of Transportation in 1989. The Indiana Toll Road is owned by the state but has been placed under concession. Between 2005 and 2015, the Major Moves program was implemented, with a $2.8 billion significant upgrade of the road network, with 87 new roads and 772 kilometers of new road, plus 60 new or upgraded connections. Also, 25% of all bridges were replaced between 2006 and 2016.

Special is the place Carmel, a large suburb north of Indianapolis. A large concentration of roundabouts has been constructed here in a short period of time. In 2016, Carmel had 94 roundabouts.

  • Bittranslators: State overview of Indiana, including geography, economy, population and history as well as introduction to major cities of Indiana.

Interstate Highways

Several Interstate Highways cross Indiana, many converge in Indianapolis. Interstate 64 is the east-west route through the south of the state, while Interstate 65 is the north-south route of the state, connecting the major cities of Louisville, Indianapolis and Chicago. This is a crucial transport corridor. Interstate 69 forms an incomplete diagonal route through the southwest, center, and northeast of the state. This is the main route to Michigan and Canada. Interstate 70 runs east-west through the center of the state. The Interstate 74 does that too, but runs a bit more diagonally and is, among other things, the connection between Indianapolis and Cincinnati. Interstate 80 and Interstate 90 largely converge to form the Indiana Toll Road as an east-west route through the north of the state, from the Chicago area through South Bend to Ohio. Interstate 94 runs around Lake Michigan and is part of the connection between Chicago and Detroit.

In addition, there are a number of auxiliary routes of the Interstate Highways. Interstate 265 forms the northern portion of the Louisville, Kentucky beltway. Interstate 275 runs a short distance through Indiana and is part of the Cincinnati, Ohio ring road. Interstate 465 forms the Indianapolis beltway, and Interstate 469 forms the bypass of the northeastern city of Fort Wayne. Finally, Interstate 865 forms a short connection in northwest Indianapolis.

Indianapolis has a reasonable capacity urban highway network, most highways in the urban core have 2×3 lanes, but the I-465 around the city is generally wider, with 2×4 to 2×6 lanes. Only I-65 and I-70 converge in downtown, I-69 and I-74 are rerouted outside Indianapolis, over I-465.

  • Deluxesurveillance: Nickname of Indiana as The Hoosier State. Also covers geography, history, economy, politics and administration of the state.

US Highways

In addition, Indiana’s secondary road network is well developed. Several US Highways are a 2×2 divided highway over longer distances:

  • US 24 Logansport – Fort Wayne 110 km
  • US 30 Dyer – Fort Wayne 245 km
  • US 31 Columbus – Indianapolis – South Bend 300 km
  • US 40 Terre Haute – Indianapolis – Richmond 200 km
  • US 41 Evansville – Hammond 525 km
  • US 52 Fowler – Lebanon 120 km

The network of 2×2 divided highways is larger in Indiana than in the neighboring states of Illinois and Kentucky. US 31 is partly a freeway and is sometimes suggested as a candidate for an Interstate Highway, with I-67 being the most obvious.

State Roads

The state has a dense network of state routes or state roads. The roads are numbered in the same way as US Highways, with odd numbers with one or two digits running north-south and increasing in numbering west, and even numbers with one or two digits forming east-west routes, running north to west. ascend to the south. The three-digit numbers are related to the one- and two-digit state routes or US Highways. The routes are numbered from 1 to 999, but many of the higher numbers are skipped. If there is a US Highway running through the state, a state route will not be given that number.

A small number of state roads are freeways;

  • SR-25: Lafayette – Logansport
  • SR-100: in Indianapolis
  • SR-431: Indianapolis-Carmel
  • SR-641: Terre Haute
  • SR-912: Hammond-Gary

Toll roads

The state’s primary toll road is the Indiana Toll Road, which runs east-west through the north of the state. I-80 and I-90 run on the Indiana Toll Road. The Chicago Skyway is also partly located in Indiana. State Route 912 in East Chicago is also to become a toll road. Indiana is affiliated with the E-ZPass group.


The land of Indiana is largely in a grid divided, with an intersecting road every mile. In the 19th century these were barely maintained dirt roads. Road building was a task of the counties and cities. In 1919, the Indiana State Highway Commission was established with the task of developing a highway network in the state. Indiana was relatively late in taking charge of road construction, in many other states it was 10 to 15 years earlier. At the time, Indiana had identified only a few routes to develop. This was a north-south route from Louisville via Indianapolis to South Bend, which largely coincided with the later US 31, an east-west route north from Dyer via Valparaiso and South Bend to Fort Wayne, which coincided with US 30, US 20, US 33 and US 30, an east-west route through the middle of the state,

In 1923 there was only one long tarmac road in Indiana, the east-west route through the middle of the state, which would later become US 40. Even then it was clear that Indianapolis was an important city for through traffic. Elsewhere, there were only stretches of tarmac road around Fort Wayne and South Bend, as well as multiple approach roads from Indianapolis. During the 1920s many major roads were paved, especially with the introduction of the US Highways in 1926 it became clear which routes had priority to be paved. By 1929, traffic from Indianapolis could move in 13 directions on tarmac roads. The network of tarmac roads was clearly more extensive in northern Indiana than in southern Indiana. In the 1930s, the south of the state caught up.

Indiana’s first highway was built in the early 1950s, the Borman Expressway (then State Road 420) near the Illinois border and opened to traffic in 1952. Later this became I-80/94. Shortly thereafter, development began on a series of toll roads between New York City and Chicago. In Indiana, the Indiana Toll Road was built for this purpose, which was built very quickly through the north of the state and opened to traffic in phases between August and November 1956. With this, Indiana already had more than 250 kilometers of highway in one fell swoop. I-80/90 later rerouted onto the Indiana Toll Road.

In 1956, the system of Interstate Highways was created, which allowed Indiana to build its network of freeways. Priority had I-65 and I-70 as primary north-south and east-west routes through Indiana. I-70 was especially important, US 40 had already largely been widened to 2×2 lanes by then, and I-70 would run parallel to it. The last section of both highways was the joint section near downtown Indianapolis that opened in 1976. This was not the first completed Interstate Highway, however, in 1967 the last section of I-74, Indiana’s first completed highway, opened. In 1970, I-465 was completed as an Indianapolis bypass. Not long after, in 1971, I-69 was completed between Indianapolis and the Michigan border.

Few new highways have been built since 1976, but parts of US 31 between Indianapolis and South Bend have been converted into freeways. The St. Joseph Valley Parkway around South Bend is quite old, the section of US 31 was completed in 1970. More recently, portions of US 31 have been further converted to freeway, around Kokomo in 2013, between Plymouth and South Bend in 2014, and in the northern suburbs of Indianapolis in 2015. Another focus was the construction of I-69 between Evansville and Indianapolis. This was not part of the original Interstate Highways plan, but I-69 was developed as a long-haul route from the Mexico border to the Canada border. In 2012, a 108-kilometer section of I-69 opened in the southwest of the state, one of the largest road openings in the United States in half a century. I-69 also absorbed the former I-164 around Evansville. I-69 is not yet completed.

Indiana Road Network