Today was a visit to Quake Lake. It is a sad story. None of us were aware of the earthquake that happened in 1959. Quake (officially Earthquake Lake) is a lake in southwestern Montana. It was created from an earthquake on August 17, 1959, right before midnight killing 28 people. Quake Lake is 190 feet deep and 6 miles long.
The earthquake measured 7.5 and caused an 80-million ton landslide. This landslide created a dam on the Madison River. The landslide traveled down Sheep Mountain, at an estimated 100 miles per hour (160 km/h), killing 28 people who were camping along the shores of Hebgen Lake and downstream along the Madison River.
Upstream the earthquake forced the waters of Hebgen Lake to shift violently. The lake dropped by 20 ft. There was a threat that water would overflow the dam backwards. An overflow spillway was quickly created to handle the additional water and flooding in the next few days. Several geysers in the northwestern sections in Yellowstone National Park erupted and numerous hot springs became temporarily muddied.
Within the immediate vicinity of the earthquake and resultant landslide, a few dozen cabins and homes were destroyed. Some cabins floated away with people jumping to the shore. It generated hurricane force winds causing more havoc. The landslide crushed some of the cabins. The highway dropped several feet.
The park is free and was tastefully done. It told the story well. The ruins from the cabins were still on the lake side. It was a sobering experience to think of what happened.
Earthquake Center 
Overflow Spillway 
Hebgen Lake 
Old highway and ruins 
Ruins of a cabin 
Earthquake Lake with ghost trees