Caribou, sand dunes, the Kobuk River, Onion Portage - just some of the facets of Kobuk Valley National Park. Half a million caribou migrate through, their tracks crisscrossing sculpted dunes. The Kobuk River is an ancient and current corridor for people and wildlife. For 9000 years, people came to Onion Portage to harvest caribou as they swam the river. Even today, that rich tradition continues.