The National Elk Refuge provides, preserves, restores, and manages winter habitat for the nationally significant Jackson Elk Herd as well as habitat for endangered species, birds, fish, and other mammals. Located in the heart of the 22-million acre Greater Yellowstone Ecosystem, the National Elk Refuge provides critical habitat for a number of species, including elk, bison, pronghorn, swans, eagles, and trout. The refuge is six miles wide at its widest point and ten miles long from southwest to northeast. The elevation varies from 6,200 feet to 7,200 feet. The Teton Range, visible to the west, rise to 13,775 feet at the summit of Grand Teton. The valley and surrounding mountains show classic examples of glaciation.