Indian Lake is a reservoir in Logan County, western Ohio, in the United States. It is approximately 20 miles (32 km) southeast of Lima. It is fed by the north and south forks of the Upper Great Miami River, Cherokee Mans Run, Blackhawk Creek, and Van Horn Creek. The outlet of the lake, at the bulkhead or "spillway" built in the 1850s by Irish laborers, is the beginning of the Great Miami River. At 5,104 acres (2,066 ha), Indian Lake is the second largest inland lake in Ohio.

State Route 366 is an east–west state highway in the western portion of the U.S. state of Ohio. SR 366 has its western terminus at a T-intersection with U.S. Route 33 nearly 1.50 miles (2.41 km) northwest of Lakeview. The route's eastern terminus is at State Route 117 about 1.50 miles (2.41 km) north of Huntsville. SR 366 runs along the western and southern edge of Indian Lake and provides access to homes and recreational facilities along the lake shoreline. SR 366 was designated in 1939, and was extended in 1961.