| Alamosa River | |
| Name origin: "of cottonwood" | |
| Country | United States |
|---|---|
| State | Colorado |
| Source | |
| - coordinates | [1] |
| Mouth | Rio Grande |
| - location | arid land south of Alamosa |
| - coordinates | [1] |
| Length | 64 mi (103 km), west-east |
| Basin | 148 sq mi (383 km2) |
The Alamosa River is a river in the southern part of the U.S. state of Colorado. It is about 64 miles (103 km) long,[2] flowing roughly east through the San Luis Valley. Its watershed comprises about 148 square miles (380 km2).
The river's name means "shaded with cottonwoods" in Spanish.[3]
The river was affected by the Summitville mine disaster, the worst cyanide spill in United States history.