Tongue River Reservoir State Park is a state park and public recreation area on the western shore of the 12-mile-long Tongue River Reservoir a few miles north of Decker. Surrounded by the vast open prairies and densely forested canyons of southeastern Montana, the 642-acre park boasts breathtaking landscapes and offers an array of outdoor and recreational activities, ranging from boating, fishing, and swimming to camping, hiking, and wildlife viewing.. The park also offers camping with electrical hookups, and there is a golf course, and two museums are located nearby in Sheridan.

Decker, MT 59025, Phone: 406-757-2298

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