SR 366 has its western terminus at a T-intersection with U.S. Route 33 (US 33) nearly 1.50 miles (2.41 km) northwest of Lakeview.

The entirety of SR 366 is located within the northwestern quadrant of Logan County.

It moves east, meets SR 235, and becomes concurrent one mile later.

The concurrency parallels the shore of Indian Lake until SR 235 splits off in Lakeview.

[2][3] By 1961, a new two-lane alignment of US 33 was established through Lakeview, Russells Point and to the southeast.