Hikers trek out in the Great Sand Dunes National Park in the San Luis Valley of Colorado. Made a national park in 1932, the dunes are the tallest in North America. Human habitation in the San Luis Valley stretches back over 11,000 years.
Hikers trek out in the Great Sand Dunes National Park in the San Luis Valley of Colorado. Made a national park in 1932, the dunes are the tallest in North America. Human habitation in the San Luis Valley stretches back over 11,000 years.