San Luis is widely called Colorado's oldest town, settled in 1851

San Luis, the county seat of Costilla County, has a strong claim to being the oldest town in Colorado. State sources put its founding at 1851, which is years before Colorado became a territory or a state. History Colorado and the National Park Service both describe it as Colorado’s oldest town.

The town did not grow up around a gold strike or a railroad, the way many Colorado towns did. It was settled by Hispano families who moved north from the Taos area of New Mexico onto the Sangre de Cristo Land Grant. They built homes and fields along Culebra Creek and shared water and common land in the old village way. That is why San Luis feels different from a mining-era town: it grew from farming and community, with a plaza at its center.

Knowing this helps a newcomer make sense of the place. The Spanish place names, the adobe buildings, the long fields by the creek, and the deep local roots all come from this early founding. It is one of the things that makes Costilla County distinct in Colorado.

To read the founding story from a careful source, see History Colorado’s account of Colorado’s oldest town.