DeLong Mountains, Brooks Range. The cold spring and wet summer in the Alaskan Arctic caused floods that swept away villages in the Koyukuk. While studying the western arctic caribou herd with its record 600,000 members, we crossed the DeLong Mountains from the Kokolik River to the Naniviksak and descended the entire Kugururok to Noatak village. Copter Peak at the Naniviksak headwaters appears to be a volcanic plug. We made its first ascent from the east. The black chert and obsidian are a source area for the arctic small-tool cultures of the region.

Dennis Schmitt, Sierra Club