The Sangre de Cristo Range is a mountain range in the Rocky Mountains in southern Colorado in the United States, running north and south along the east side of the Rio Grande Rift. The mountains extend southeast from Poncha Pass for about 75 mi (121 km) through south-central Colorado to La Veta Pass, approximately 20 mi (32 km) west of Walsenburg, and form a high ridge separating the San Luis Valley on the west from the watershed of the Arkansas River on the east. The Sangre de Cristo Range rises over 7,000 ft (2,100 m) above the valleys and plains to the west and northeast.

The San Luis Valley is a region in south-central Colorado with a small portion overlapping into New Mexico. The valley is approximately 122 miles (196 km) long and 74 miles (119 km) wide, extending from the Continental Divide on the northwest rim into New Mexico on the south. It contains 6 counties and portions of 3 others. It is an extensive high-elevation depositional basin of approximately 8,000 square miles (21,000 km2) with an average elevation of 7,664 feet (2,336 m) above sea level. The valley is a section of the Rio Grande Rift and is drained to the south by the Rio Grande, which rises in the San Juan Mountains to the west of the valley and flows south into New Mexico. The San Luis Valley has a cold desert climate but has substantial water resources from the Rio Grande and groundwater.