Costilla County, Colorado

Costilla County is the ninth-least populous of the 64 counties in the U.S. state of Colorado. As of the 2010 census, the population was 3,524. The county seat is San Luis, the oldest town in Colorado.

Costilla County, Colorado

Costilla County is the ninth-least populous of the 64 counties in the U.S. state of Colorado. As of the 2010 census, the population was 3,524. The county seat is San Luis, the oldest town in Colorado.