Lakes / Montana / Thornton Lake
Thornton Lake, Montana
29.1 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Montana
46.26 degrees N, 113.04 degrees W - Granite County. State and county outlines drawn from Census boundary data; the lake marker is placed by its Montana Fish, Wildlife & Parks coordinates, not by eye. Schematic - not a survey map.
Facts and Figures
Waterbody ID81310371
CountyGranite
Coordinates46.2589, -113.0386
Largest Lakes in Montana
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Fort Peck Lake | Valley | 233,053 acres | - |
| 2 | Flathead Lake | Lake | 122,132 acres | About 380 ft |
| 3 | Canyon Ferry Lake | Broadwater | 32,773 acres | About 170 ft |
| 4 | Lake Koocanusa | Lincoln | 28,723 acres | - |
| 5 | Hungry Horse Reservoir | Flathead | 23,577 acres | - |
Sources: USGS NHD lake data (ID 81310371). Verified October 30, 2026.