Kobuk Valley National Park  

You don’t expect vast sand dunes and 90-degree summer temperatures in the arctic, but you’ll find them here, in the 25-square mile expanse known as the Great Kobuk Sand Dunes. Every spring and fall, hundreds of thousands of caribou migrate through the park. Onion Portage is full of archeological sites that reveal human occupation in the Kobuk Valley over the past 12,500 years.

Size: 1.7 million acres. Located in northwest Alaska, about 100 miles east of Kotzebue.

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