Lake Bonneville was a large prehistoric lake that existed during the last Ice Age, covering much of present-day Utah, Nevada, and Idaho. It formed around 30,000 years ago and reached its maximum size about 15,000 years ago, when it was approximately 1,000 feet deep. As the climate warmed, Lake Bonneville began to shrink, eventually splitting into smaller bodies of water, including the Great Salt Lake. Today, remnants of this ancient lake can be seen in the surrounding landscape, which features unique geological formations and a rich history of human habitation.