Costilla County, Colorado

Costilla County sits at the southern end of Colorado’s San Luis Valley, along the New Mexico border. San Luis, the county seat, is the oldest continuously inhabited community in Colorado. The county is mostly rural, with wide-open spaces and impressive mountain views.

Farming and ranching are the main industries, with the Rio Grande and Culebra Creek providing important water resources for irrigation. Hunting and fishing also attract visitors looking to enjoy the area’s quiet landscapes and outdoor recreation.

Costilla County has deep Hispanic roots, with some families tracing their history back to the region’s early Spanish settlers. The Sangre de Cristo Mountains rise along the eastern side of the county, while Great Sand Dunes National Park and Preserve is located nearby. The combination of historic communities, agriculture, and dramatic scenery gives Costilla County a distinctive character.

County NameCostilla CountyCounty SeatSan LuisPopulationApproximately 3,700Cities, Towns, and CommunitiesSan Luis, Blanca, Fort Garland, La JaraInterstates and HighwaysUS 160, CO 159FIPS Code08-023Total Area (Land and Water)1,221 square miles (Land: 1,219 sq mi, Water: 2 sq mi)Adjacent Counties (and Direction)Huerfano County (Northeast), Las Animas County (East), Colfax County, New Mexico (Southeast), Taos County, New Mexico (South), Conejos County (West), Alamosa County (Northwest)Time ZoneMountain Standard Time (MST)StateColoradoCoordinates37.2440° N, 105.4000° WEtymologyNamed after the Costilla River, which translates to “rib” in SpanishMajor LandmarksThe Sangre de Cristo Mountains, Great Sand Dunes National Park
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