In the Kobuk Valley National Park, a remarkable and unexpected marvel awaits adventurers – the Great Kobuk Sand Dunes. Known as the least visited National Park, these towering sand dunes, the largest active ones in the Arctic, rise unexpectedly from the tundra and the surrounding trees, creating a vast expanse of shifting golden sands that seem out of place 35 miles above the Arctic Circle, as if they were plucked from the Sahara itself.

But these dunes are not a mere geological quirk; they are a living relic of Earth’s distant past. Over 28,000 years ago, as the Earth cooled and glaciers began to form, these dunes began their slow formation. The glaciers, with their relentless advance and retreat, ground the surrounding rocks into fine sand, which the wind carried into the sheltered Kobuk Valley. When the glaciers finally began their retreat some 14,000 years ago, they left behind a stunning 200,000 acres of rolling sand dunes along the banks of the river. However, the relentless march of time and nature has seen vegetation reclaim all but 16,000 acres of these sandy giants. Sparse grasses, sedges, wild rye, and unique flora like the Kobuk locoweed have found a home in the ever-shifting sands, stabilizing them and paving the way for mosses, algae, lichen, shrubs, and eventually the sturdy aspen, birch, and spruce of the surrounding forest.

The dunes, despite their seemingly harsh environment, teem with life at their fringes. Black and grizzly bears, wolves, foxes, porcupines, and moose make their homes in the adjacent woods and tundra. Signs of their passage, like tracks etched in the sand, serve as a testament to their presence. Most notably, the grand Western Arctic Caribou Herd traverses the Kobuk Valley twice a year during their epic migration to and from their calving grounds north of the Brooks Range. Spring and fall bring with them the spectacle of the caribou’s hoof prints marking the sands of the Great Kobuk Sand Dunes. Humans, too, have left their mark on Kobuk Valley’s dunes for millennia. For at least 8,000 years, people have called this place home, living primarily along the banks of the fish-filled Kobuk River. Yet, they also relied on the unique landscape of the sand dunes to hunt large animals. Evidence of their hunting camps, dating back thousands of years, can still be found dotting the dune’s edge.

Today, the Great Kobuk Sand Dunes remain a breathtaking spectacle, the largest and most accessible of the three dune fields, spanning 25 square miles just a stone’s throw from the Kobuk River. Towering dunes, some reaching heights of 100 feet, command attention, and even in the Arctic, summer temperatures can soar to a surprising 100 degrees. Visiting these dunes is an unforgettable experience, but it comes with a responsibility to be well-prepared for a backcountry adventure and to show respect for the Native inholdings and local subsistence practices that have long been part of the region’s history.

For those who dare to explore, the Great Kobuk Sand Dunes offer an array of experiences depending on the time of year. Whether it’s hiking through the dunes in the heat of summer or witnessing the majestic caribou migration in the crisp days of fall, these sands hold secrets and stories that make them a truly special place for all who venture here.

Photos courtesy of Alaska Photo Graphics, National Parks Service, NASA Earth Observatory and Atlas Obscura.