Haystack Mountain is a prominent granite summit in Wyoming’s remote Wind River Range, rising 11,978 feet in the Bridger Wilderness near the Continental Divide. Its steep northwest face climbs nearly 2,000 feet above Clear Lake in half a mile, and runoff from the mountain feeds the Big Sandy River headwaters. Reached most often by the Big Sandy Trail, it lies in an alpine subarctic climate with long snowy winters, short storm-prone summers, and hazardous conditions shaped by altitude and exposure. The peak is also an established climbing destination, with routes recorded from 1958 through 2010, giving it significance as both striking wilderness terrain and serious technical granite climbing.