Kobuk Valley Dunes Approach

The Great Kobuk Sand Dunes form the largest active sand dune field in the Arctic, covering 25 square miles of the Kobuk River valley with dunes reaching 100 feet in height — a seemingly impossible Arctic desert 35 miles above the Arctic Circle. The dunes are a glacial relic: fine quartz sand ground from bedrock by Pleistocene glaciers was deposited in the valley and has been repeatedly reworked by wind into the classic barchan and transverse dune forms more typically associated with the Sahara or Arabian Peninsula. Surface temperatures on the dunes can reach 100°F on summer days even as temperatures a few miles away remain in the 40s. The approach route from a floatplane landing on the Kobuk River crosses cottonwood-and-spruce floodplain forest and wet tundra before the vegetation abruptly gives way to bare sand. Caribou trails and tracks are imprinted in the dune faces; the Western Arctic herd uses dune corridors during migration to escape insects. Ancient artifacts — spear points, scrapers, and hearth remnants — have been recovered from dune blowouts, representing 12,500 years of human use of this unique Arctic landscape.