The entire route is rural two-lane highway that passes through farmland, residential and commercial properties.

No segment of State Road 121 in Indiana is included in the National Highway System (NHS).

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

This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year.

[4] The southern segment of SR 121 begins at US 52 and heads north as a rural two-lane curvy highway.

The highway passes through mostly farmland and enters the town of Laurel, making a few sharp curves.