Which National Park Service park protects North America’s tallest sand dunes?

Great Sand Dunes National Park and Preserve protects North America’s tallest sand dunes.

The dunes rise from Colorado’s San Luis Valley against the Sangre de Cristo Mountains. The highest dunes reach about 750 feet, while the dune field covers roughly 30 square miles. Wind from the valley carries sand toward the mountains, and opposing winds help build the dunes upward.

Water also plays an important role. Medano and Sand Creeks transport sediment around the dune system, helping recycle sand back toward the field. The result is a landscape containing dunes, grasslands, wetlands, forests, alpine lakes, and high mountain tundra.

The area was first protected as Great Sand Dunes National Monument in 1932. Congress authorized a boundary change and national-park-and-preserve designation in 2000, and the present national park and preserve were established on September 24, 2004.