Earthquake Lake Geologic Area is on US 287, 17 mi. n.w. of jct. US 191, in the Hebgen Lake Area. This 37,800-acre tract embraces Hebgen and Earthquake lakes. Traces remain of the 1959 earthquake, which blocked a river, moved huge boulders and tilted a lake bed. An observation room features a DVD presentation telling the story of the quake. The visitor center contains a working seismograph.