The Brooks Range stretches across the entirety of Northern Alaska, from the Chukchi Sea to the Yukon border. From the range's northern slopes, the Arctic Coastal Plain stretches to the Arctic Ocean. Elevation in the range averages around 7,000 feet, rising to over 9,000 feet in the extreme northeast. The higher slopes are snow and ice-clad for much of the year, and they drain into icy rivers which flow into icy seas. The character of this great land is of profound remoteness, where the only sounds are from the winds sweeping across the peaks. Wolves, moose, and a 160,000-strong porcupine caribou herd roam the uplands of the range. Nineteen million acres are presently preserved in the Arctic National Wildlife Refuge, though its protected status has recently come under a series of attacks by those seeking to open the refuge for oil drilling. The highest peak of the Brooks Range is Mount Isto (9,060 ft./2762 m).