Southern Colorado's unique Great Sand Dunes rise to a height of 750 feet above the San Luis Valley floor and are the nation's highest dunes not adjacent to an ocean or lake. The sweeping dunes were protected as a national monument in 1932 and as a national park in 2000. From prehistoric hunter-gatherers to the historic Ute Indian tribe, inhabitants have long used the resources of the land around the dunes. Zebulon Pike was the first American explorer...