"The Arctic National Wildlife Refuge protects the most spectacular array of arctic plants, wildlife, and land forms in the world. Designed to embrace the range of the great Porcupine caribou herd, the Arctic is also home to free-roaming herds of muskox, Dall sheep, packs of wolves, and such solitary species as wolverines and polar and grizzly bears. Why this concentration? Well, even though the refuge is immense, the habitats are actually extremely compressed. The highest mountain lies just 50 miles from the sea coast. In between range the lower peaks, glacial valleys, foothills, and the fabled coastal plain.
The coastal plain comprises the smallest part of the refuge, but it is biologically the most important. This 25-mile wide strip of of tundra is the birthing ground of not only the caribou but also polar bears, grizzlies, Arctic wolves, and the highly endangered shaggy musk ox.
The Brooks Range serves as the backbone of the refuge. This range is the northernmost extension of the Rocky Mountain chain. It stretches for 600 miles in length by 200 miles in width across the entire Alaskan Arctic. "
http://gorp.away.com/gorp/resource/us_nwr/ak_arcti.htm