[3] The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation.

The road leaves Knox passing through the east side of town.

The route enters Auburn on the west side of town and has an interchange with Interstate 69(I-69).

The road now passes through commercial areas before entering downtown Auburn where it has an intersection with Old SR 427.

[7][6] In the early 1940s, the road's western terminus was at the Illinois state line, becoming Exchange Street.