The Tetons are one of the youngest mountain ranges in North America. They have been uplifting for less than 10 million years, making them “adolescent” mountains, as compared to the “middle-aged” Rockies (50-80 million years old) or the “elderly” Appalachians (more than 300 million years old).

Most of the lakes in the park were formed by glaciers and the largest of these lakes are located at the base of the Teton Range