Triple Divide Peak is located in the Lewis Range, part of the Rocky Mountains in North America. It is located in Glacier National Park in the state of Montana in the United States. The Lewis Range was formed in the Lewis Overthrust, some 170 million years ago, when an enormous slab of Precambrian rock faulted and slid over younger rocks from the Cretaceous period. The summit of the peak is the point where two of the principal continental divides in North America converge, the Great Divide and the Northern or Laurentian Divide.