In 1694, Don Diego de Vargas became the first European known to have entered the San Luis Valley, although herders and hunters from the Spanish colonies in present-day northern New Mexico probably entered the valley as early as 1598. De Vargas and his men hunted a herd of 500 bison in the southern part of the valley before returning to Santa Fe. In 1776, Juan Bautista de Anza and an entourage of men and livestock probably passed near the dunes as they returned from a punitive raid against a group of Comanches. At this time, the valley was a travel route between the High Plains and Santa Fe for Comanches, Utes, and Spanish soldiers. The dunes were likely a visible landmark for travelers along the trail.
