Fort Garland was in use for 25 years, a long time for a frontier fort. The coming of the railroad and the end of the Indian Wars brought Fort Garland’s 25 years of service to an end in 1883. After the army left, the fort’s property fell into disuse and passed through many hands over the next four decades. By the 1920s the last owner planned to raze the remaining buildings and sell them for parts. The prospect of demolition and sale spurred locals in Costilla and Conejos Counties to form the Fort Garland Historical Fair Assoc. in May 1928. The purpose of the association was to preserve what remained of the fort, with the idea that the site might serve in the future as a county fairground. The association went around the San Luis Valley selling $5 shares to ranchers, farmers, and businesspeople. This fundraising effort enabled the association to buy Fort Garland in 1929. Just then, however, the Great Depression hit, and the association struggled to pay taxes on the property throughout the 1930s and early 1940s.
In 1945 the Colorado Historical Society acquired the site. By that time all but five of the original twenty-two buildings had been demolished or had deteriorated beyond repair. The five remaining buildings were restored with new roofs, adobe bricks, and interior fittings, and the restored Fort Garland opened as a museum in 1950.
Fort Garland continues to operate as a regional museum of History Colorado and is devoted to the history of the San Luis Valley.