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.
Tierra Amarilla is a census-designated place in and the county seat of Rio Arriba County, New Mexico, United States.
Costilla County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 3,499. The county seat is San Luis, the oldest continuously occupied town in Colorado.
Fort Garland is an unincorporated town, a post office, and a census-designated place (CDP) located in and governed by Costilla County, Colorado, United States. The Fort Garland post office has the ZIP Code 81133. At the United States Census 2020, the population of the Fort Garland CDP was 464.
San Luis is a statutory town that is the county seat and the most populous town of Costilla County, Colorado, United States. Formerly known as San Luis de la Culebra, it is the oldest continuously occupied town in Colorado. The population was 598 at the 2020 census.
The Sangre de Cristo Mountains are the southernmost subrange of the Rocky Mountains. They are located in southern Colorado and northern New Mexico in the United States. The mountains run from Poncha Pass in South-Central Colorado, trending southeast and south, ending at Glorieta Pass, southeast of Santa Fe, New Mexico. The mountains contain a number of fourteen thousand foot peaks in the Colorado portion, as well as several peaks in New Mexico which are over thirteen thousand feet.
Culebra Peak is the highest summit of the Culebra Range of the Sangre de Cristo Mountains of the Rocky Mountains of North America. The prominent 14,053-foot (4,283 m) fourteener is located on private land, 14.2 miles (22.8 km) east-southeast of San Luis in Costilla County, Colorado, United States. Culebra Peak is the southernmost fourteener in the range.
Agate is an unincorporated community and U.S. Post Office in Elbert County, Colorado, United States. The ZIP Code of the Agate Post Office is 80101.
Bedrock is an unincorporated community and U.S. post office in western Montrose County, Colorado, United States. The ZIP code of Bedrock is 81411.
San Pablo is an unincorporated community located in Costilla County, Colorado, United States. The San Luis post office (Zip Code 81152) serves San Pablo postal addresses. San Pablo is located in the Rio Culebra valley of the Sangre de Cristo Land Grant which was awarded to the family of Carlos Beaubien in 1843.
San Acacio is an unincorporated community and a census-designated place (CDP) located in and governed by Costilla County, Colorado, United States. The population of the San Acacio CDP was 56 at the 2020 United States census. The Sanford post office serves San Acacio postal addresses.
Rio Culebra is a river or creek in Costilla County, Colorado. The Rio Culebra rises in the Sangre de Cristo Mountains and is 48 km (30 mi) long. It empties into the Rio Grande west of the town of San Luis. The region around San Luis features extensive agriculture made possible by irrigation water from the river. Sometimes called the "Culebra Basin" this area is known for the extensive irrigation canals called acequias built by its Hispanic settlers in the 19th century and still in use in the 21st century
The San Luis Bridge, also known as State Bridge or Bridge over Culebra Creek, is a historic open spandrel arch bridge that crosses Culebra Creek in San Luis, Colorado. It was built in 1911 as a road bridge, but now serves pedestrian traffic. It is listed on the National Register of Historic Places.
Costilla is a census-designated place in Taos County, New Mexico, United States. Its population was 205 as of the 2010 census. Costilla has a post office with ZIP code 87524. State roads 196 and 522 intersect in the community.
The Los Caminos Antiguos Scenic and Historic Byway is a 129-mile (208 km) Back Country Byway and Colorado Scenic and Historic Byway located in Alamosa, Conejos, and Costilla counties, Colorado, USA. The byway explores the historic San Luis Valley of south-central Colorado including Great Sand Dunes National Park and Preserve; the Old Spanish National Historic Trail; historic Fort Garland, San Luis (San Luis de la Culebra), the oldest town in Colorado; and the Cumbres and Toltec Scenic Railroad.
The Sangre de Cristo Land Grant in the San Luis Valley of southern Colorado and northern New Mexico consists of 1,000,000 acres (4,000 km2) of mostly arid land. It was awarded by the government of New Mexico to the Beaubien family in 1843. The land grant was originally settled by Hispanics from New Mexico. Since the incorporation of the area of the grant into the United States in 1848, legal disputes between the descendants of the Hispanic settlers and Anglo ranchers about ownership of and access to some of the land in the grant area have been frequent and continued into the 21st century.
Rito Seco is a tributary of Culebra Creek in Costilla County, Colorado. The name means dry creek in the dialect of Spanish spoken in southern Colorado and New Mexico.
United States 
State of Colorado 
