Information on Indiana's historic highways and highway system

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     Interstate Highway History
     U.S. Highway History
     State Highway History
     National Historic Routes and Trails
     Scenic Byways

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     Indiana Highway Ends


Indiana's Highway system has had many changes over the years. The original US highways are still pretty much in the same places as they were originally, and many newer US highways were commissioned over the years. State roads date back to 1918 and underwent a major renumbering when US highway routes were introduced in the state in 1926. Interstate highway construction began and began providing better alternate routes to the US highways and state roads they replaced. The current interstate highway system is pretty much the same way it was when it was first laid out. We begin with the Interstate system in Indiana...


Highways replaced by Interstates
Route # Routes Replaced
I-64 IN 62, IN 66
I-164 US 41, IN 57
I-65 US 31, US 41, US 52
I-265 IN 62
I-465 IN 100
I-865 I-465 Northwest Spur
I-69 US 27, IN 37, IN 67
*IN 54, *IN 57, *I-164
I-469 N/A
I-70 US 40
I-74 US 36, US 136, US 52,
US 421, IN 46
I-80 US 20, Lincoln Hwy
I-90 US 20, Lincoln Hwy
I-94 US 12

*Once I-69 is extended south to Evansville.

Indiana's Interstate system was constructed beginning in the late 1950's and early 1960's. Currently Indiana's interstate system consists of 8 primary interstate highways located in indiana, However there are only actually 7 highway alignments since I-80 is cosigned with I-94 and then I-90 across the state. There are also 5 secondary (three-digit) interstate highways looping around or spuring into cities across Indiana.

Originally I-65 was temporarily routed around Indianapolis onto the West and South legs of the I-465 loop until the interstate was eventually constructed through downtown, Interstate 74 was also routed around along the west and south legs as well and still uses this routing as plans to bring I-74 through town never materialized. Plans to build a freeway along Binford Blvd to downtown were also abandoned; originally intending to extend I-69 to downtown indy at the north split. The plans were later revised to a freeway spur known as I-165 which would have purportedly ended at the Keystone Ave intersection, but those plans were scrapped also.

An interstate numbering anomaly occured was with I 465. Originally I-465 was designed to be a closed loop system, as it is now, but when first constructed the northwest section of the loop between I-65 interchange and 96th Street was not built. Instead I-465 headed west into Boone county and ended at the wye interchange at I-65 west of Zionsville. Eventually the gap in the loop was closed creating the complete I-465 route but leaving the spur portion numbered as I-465 as well, it created a loop/spur route with a confusing three-way interchange. The spur portion of the loop has since been renumbered as I-865, which makes much more sense and has eliminated the confusion.

The Borman Expressway and Indiana Toll Road also had a change in route numbers. Originally the Indiana Toll Road was designated as I-94 west of the lake station interchange, and I-80/90 to the east. The Borman Expressway was then cosigned as I-80, I-90 & I-294 west of the Lake Station Interchange. In 1965, the western ends of interstates 90 and 94 swapped places allowing I-90 run the entire length of the Indiana Toll Road and I-94 run the entire length of the Borman Expy, then continue east into Michigan. The interstate 80 routing remained the same, and I-294 was truncated to its current terminus at the Kingery Expressway in Illinois.

To see examples of historical interstate markers used see the Route Markers page.


Indiana's U.S. Routes were part of the first transcontinenntal highway system built in the U.S. These highways were laid out the AASHO (American Association of State Highway Officials), which was responsible for approving and assigning routes and route numbers. Initially ASSHO assigned split U.S routes (ie. 31E/31W as in Kentucky) but there were not any known signed split routes within the state. A few US highways have been decommissioned and have since been reassigned state road numbers. Most of the historic US highways still exist on their original alignments. in some more urbanized areas bypasses route the highways around town. This is most evident in in Indianapolis where US highways that used to go thru the heart of downtown are now circularly routed around town on I-465.

For a list of current and former U.S. routes in Indiana including general history about each of Indiana's U.S. highways. Click Here" target="_blank" alt="hwy explorer: Indiana Highway Ends">Highway Explorer is also a good site to refer to for historical facts and even maps of former US routes. Also see


Indiana's state road system has been in existence since the first numbered signed routes were posted back in 1918. The highway system was completely renumbered in 1926 when US routes made their debut in Indiana. Since then minor changes have been over the years. Some state roads have been truncated, others renumbered and even some new highways, like SR 641 in Terre Haute. Some state roads have gone out of existence entirely, such as like IN-431 and IN-334 which were just recently decommissioned in the last few years.

Highway Explorer is a good site to refer to for historical facts and maps of current and former state roads.


Indiana had many auto trail routes during the adventof automobile travel across the united states. Many of these trails or roads were very rudimentary. Improved surfaces could consist of compacted gravel, macadam, wooden planks, and concrete. Probably the most prominent and well known auto trail is the Lincoln Highway, much of which is now US-30. Additionally roads like the National Road, or National Old Trails Road (US-40) were also well known and well travelled. Other historical routes include: The Dunes Highway in Northwest Indiana, Hoosier Way, Pikes Peak Ocean to Ocean Highway, Range Line, National Roosevelt Midland Trail, Dixie Highway, Michigan Road, and many more.


There are a few scenic Byways in Indiana. The most notable of the byways is the Historic National Road Historic Byway, and the Ohio River scenic byway. There is also a new byway known as the Whitewater Canal scenic byway, which follows along the historic Whitewater Canal, for more information visit click here.

For more info about scenic byways in Indiana visit America's or National Scenic Byways@wikipedia.