1965 Map of Blanca SE

About this map

San Luis Hills rise from the high desert floor in this mid-1960s study of Costilla County. The landscape is defined by its arid, geological character, where the prominent Sangre De Cristo and Basaltic Hills frame a territory shaped by water management and topographical markers. The presence of the Trinchera Canal and Trinchera Creek in the northern reaches indicates the critical role of irrigation and drainage in this portion of the San Luis Valley. This map, later updated in 1982, captures a sparse but structured environment where human activity is mostly limited to infrastructure like the Substa and various benchmark stations. For those studying the physical history of the valley, the detailed contour lines and landforms provide a precise look at the terrain before modern development shifted the agricultural and infrastructural footprint of the region.