Fort Concho is a former United States Army installation and National Historic Landmark District located in San Angelo, Texas. It was established in November 1867 at the confluence of the North and South Concho Rivers, on the routes of the Butterfield Overland Mail Route and Goodnight–Loving Trail, and was an active military base for the next 22 years. Fort Concho was the principal base of the 4th Cavalry from 1867 to 1875 and then the "Buffalo Soldiers" of the 10th Cavalry from 1875 to 1882. The troops stationed at Fort Concho participated in Ranald S. Mackenzie's 1872 campaign, the Red River War in 1874, and the Victorio Campaign of 1879–1880. The fort was abandoned in June 1889, and over the next 20 years was divided into residences and businesses, with the buildings repurposed or recycled for their materials. Efforts to preserve and restore Fort Concho began in the 1900s and resulted in the foundation of the Fort Concho Museum in 1929. The property has been owned and operated by the city of San Angelo since 1935. Fort Concho was named a National Historic Landmark on July 4, 1961, and is one of the best-preserved examples of the military installations built by the US Army in Texas. The Fort Concho Historic District covers the fort's original grounds and 23 buildings, some of which are the oldest in San Angelo. , about 55,000 people visit the fort annually. Operation by the US military Fort Concho was established during the American colonization of Texas in the 19th century, a process that began in the 1820s with the immigration of Anglo-Americans into Spanish, later Mexican, Texas. Europeans first reached the Concho River valley in the 16th century. The Spanish established contact and then trade with the Jumano people, who inhabited the valley until they were driven out of it by the Apache peoples in the 1690s. The Apache were themselves expelled by the mid-18th century by the Comanche. However, in 1849, American colonists began crossing West Texas in large numbers to reach California, where gold had been discovered. To protect its citizens, the United States Army ordered the construction of a string of forts along the frontier's routes of travel from 1850 to 1852. Among those forts was Fort Chadbourne, established on October 28, 1852, and among those avenues was the Butterfield Overland Mail route, established in 1858 with Fort Chadbourne as one of