1980 Map of Rio Alto Peak

About this map

Rito Alto Peak and the high ridges of the Sangre de Cristo Mountains define this 1980 survey, where the boundary between Saguache and Custer counties follows the jagged continental divide. The landscape is a complex network of glacial basins and high-altitude water bodies, including Rito Alto Lake, South Crestone Lake, and Iris Lake. Human activity is concentrated along the lower elevations and through arduous mountain crossings like Hermit Pass and Venable Pass. A notable piece of historical infrastructure, the Old Railroad Grade, runs along the western base of the range near the Crestone Cem. The presence of several Prospect markings and a Gravel Pit indicates the legacy of resource exploration in the canyons of the Rio Grande National Forest and San Isabel National Forest.