(Montana)
Tongue River Reservoir State Park is a public recreation area located 6 miles north of Decker, Montana, on the western shore of the Tongue River Reservoir. The 12-mile-long reservoir is an impoundment of the Tongue River. The state park, occupying 642 acres at an elevation of 3468 feet, offers boating, fishing, camping, swimming, wildlife viewing, and a seasonal marina. (Ref: https://en.wikipedia.org/wiki/Tongue_River_Reservoir_State_Park)