[7] Formerly known as San Luis de la Culebra, it is the oldest continuously occupied town in Colorado.

San Luis was in the Sangre de Cristo Land Grant awarded by the government of New Mexico to the Carlos Beaubien family in 1843.

Colonel Christopher "Kit" Carson, Commander of Fort Garland, negotiated a treaty with the Ute people in 1867.

[10] A Pueblo Chieftain article dated June 8, 1872, describes the three stores of San Luis as kept by Fred Meyer & Co, Auguste Lacome and Mazers & Rich in addition to a blacksmith, butcher, beer saloon, carpenter and two hotels.

According to the United States Census Bureau, the town has a total area of 0.54 square miles (1.4 km2), all of it land.