Tongue River Reservoir State Park
| Tongue River Reservoir State Park | |
|---|---|
| Location | Big Horn County, Montana, United States |
| Nearest town | Decker, Montana |
| Coordinates | 45°05′59″N 106°47′40″W / 45.09975°N 106.79453°W |
| Area | 642 acres (260 ha) |
| Elevation | 3,468 ft (1,057 m) |
| Designation | Montana state park |
| Established | 1983 |
| Visitors | 99,232 (in 2023) |
| Administrator | Montana Fish, Wildlife & Parks |
| Website | Tongue River Reservoir State Park |
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.