2016 Map of Mosca Pass

About this map

Mosca Pass serves as a vital geographic divide along the border of Alamosa and Huerfano counties, where the high desert meets the eastern mountain slopes. This 2016 survey highlights the dramatic transition from the Great Sand Dunes National Park and National Preserve in the west to the dense woodlands of the Rio Grande National Forest and San Isabel National Forest. Local history is embedded in the network of historic routes, including the Mosca Pass Trail and the Ute Trail, which trace ancestral paths across the Sangre de Cristo Range. The hydrological landscape is defined by the headwaters of the Huerfano River and its numerous tributaries like Rito Oso and Sheep Cr, alongside high-elevation water management sites such as Sierra Blanco Reservoir Number 2 and Montez Reservoir.