Henrys Lake Mountains , highest point Sheep Point , el . , ( See also ) are a small mountain range northwest of West Yellowstone , Montana in Madison County , Montana . These mountains are also referred to as the Lionhead Mountains , and straddle the Continental Divide along the Idaho-Montana border . On the northwest corner of these mountains is Quake Lake , created when the 1959 Hebgen Lake earthquake caused a massive landslide and dammed the Madison River . Nine subalpine lakes sit in high cirques in the higher reaches , with several peaks topping 10,000 ' . Coffin Lake is the largest and most popular , on the Montana side . About 32,000 acres are roadless in the Montana portion , with an unknown amount in Idaho . Dense forests , pristine streams , rolling tundra , and grassy parks provide year-round habitat for grizzly bears , elk , and bighorn sheep . Rocks and soils are inherently unstable , a factor in the landslide that caused much loss of life in 1959 . The instability exists because the range is basically limestone blocks sitting on top of shale and Yellowstone volcanic rocks
1959 Hebgen Lake earthquake
1959 Hebgen Lake earthquake
Henrys Lake Mountains