I think I have posted photos of this place before. It is along U.S. 287, west of Yellowstone. The Madison River flows out of Yellowstone through Hebgen Lake, mostly pretty peacefully. This first photo shows the people floating in rafts down the river.
Just after midnight on August 17, 1959, a 7.3 - 7.5 on the Richter scale earthquake struck Madison Canyon where many people were camped or lived. One side of Hebgen lake rose 20 feet while in other places the earth subsided a similar amount. A large earth slide interrupted the flow of the river and destroyed the highway alongside it.
This caused massive flooding and caused a new lake to form, now called Earthquake Lake.
I was here a year ago, but this parking lot and the new visitor center were under construction. I was glad to be able to stop this time.
Here are some of the plaques describing the earthquake and changes to the landscape. There is a nearby memorial to the 27 people who died, many of whom were caught in the campground underneath the slide.
This is earthquake lake.
This is another place worth stopping at as you drive into Yellowstone.