Its southern terminus is at a T-intersection with SR 19 approximately 2.50 miles (4.02 km) northwest of Galion, and its northern terminus is at SR 103 in New Washington.

All of SR 602 is situated within the eastern portion of Crawford County.

No portion of this state route is included within the National Highway System (NHS).

The NHS is a network of highways identified as being most important for the nation's economy, mobility and defense.

Originally, the highway ran from its present southern terminus at SR 19 to its intersection with Old Lincoln Highway north of North Robinson.