Interstate 65 in Indiana

Interstate 65 (I-65) in the US state of Indiana traverses from the south-southeastern Falls City area bordering Louisville, Kentucky, through the centrally located capital city of Indianapolis, to the northwestern Calumet Region of the Hoosier State which is part of the Chicago metropolitan area. The Indiana portion of I-65 begins in Jeffersonville after crossing the Ohio River and travels mainly north, passing just west of Columbus prior to reaching the Indianapolis metro area. Upon reaching Indianapolis, the route alignment of I-65 begins to run more to the northwest and subsequently passes Lafayette on that city's east and north sides. Northwest of there, in west-central Jasper County, the route again curves more northward as it approaches the Calumet Region. Shortly after passing a major junction with I-80 and I-94, I-65 reaches its northern national terminus in Gary at US Highway 12/US Highway 20 (US 12/US 20, Dunes Highway) after an interchange with the Indiana Toll Road (I-90). I-65 covers 261.27 miles (420.47 km) in the state of Indiana. This is one of the principal Interstate Highways that cross the state, and, more specifically, intersect at the city of Indianapolis, that has given the state the nickname of "Crossroads of America".

I-65 enters the state northbound at Jeffersonville (across the Ohio River from Louisville, Kentucky) on the Abraham Lincoln Bridge; traffic exiting the state travels on the John F. Kennedy Memorial Bridge. I-65 travels past Clark State Forest before reaching Seymour to the north. I-65 intersects with U.S. Highway 50 (US 50), providing access to Seymour to the west. US 31 runs parallel to the Interstate until it reaches Indianapolis. North of Seymour, I-65 passes through Columbus. Just north of Columbus, I-65 runs near Camp Atterbury, an Indiana National Guard training base. The Interstate continues north into Indianapolis.

I-65 crosses the I-465 loop before reaching Indianapolis. The section of I-65 in Downtown Indianapolis overlaps I-70. The junctions are often referred to as the "North Split" and the "South Split", forming a section of Interstate locally known as the "Inner Loop" or "Spaghetti Bowl" due to the visual complexity of the overlapping freeways. The "North Split" was closed for reconstruction in early 2021 and reopened to traffic in May 2023. As part of that reconstruction, the old ramps were replaced with ones that eliminate the lane switching that drivers originally had to perform to stay on I-70 eastbound and I-65 northbound.

In 1999, the 25-mile (40 km) segment of I-65 between the two I-465 interchanges was renamed the Kenneth "Babyface" Edmonds Highway. At milemarker 116, I-65 passes Crown Hill Cemetery, burial site and memorial of former-President Benjamin Harrison. I-65 leaves the I-465 loop on the northwest side of Indianapolis. The highway travels past Eagle Creek Park and it then passes the terminus of I-865 and picks up US 52.

The segment of I-65 north of Indianapolis heads in the direction of Chicago, Illinois. US 52 runs concurrently until the north side of Lebanon; US 52 runs parallel to I-65 from this point to Lafayette, located at about the halfway point between Indianapolis and Chicago. I-65 crosses the Wabash River in Lafayette and passes next to Prophetstown State Park.

North of Lafayette, I-65 parallels US 231 and passes through the open flatlands of northwest Indiana. Protruding from the fields are some of the hundreds of wind turbines of the Benton County Wind Farm and Fowler Ridge Wind Farm. At approximately mile 199.4 is the timezone boundary between Central Time (Jasper County) and Eastern Time (White County). The Indiana Department of Transportation (INDOT) marked change in timezone with a two-sided blue sign in the center median.

Upon crossing into Lake County, over the Kankakee River, the highway is known as the Casimir Pulaski Memorial Highway. It is known as this from that point to its northern terminus. The northern terminus of I-65 is only 0.125 miles (0.201 km) north of I-90 (Indiana Toll Road) in Gary.

Like all Interstate Highways in Indiana, I-65 was constructed in segments. There were six segments in the southern portion of the state between the Kentucky border and the south leg of I-465 in Indianapolis, nine within the I-465 loop and 11 more that made up the northern portion connecting the northwest side of Indianapolis to the Indiana Toll Road (I-90) in Gary.