Established in 1855, Fort Lancaster was a large military post that was instrumental in providing protection for those passing through on the San Antonio-El Paso Road on their way to California. Today, the 82-acre site includes ruins and interpretive trail as well as a visitors center and gift shop. It is a State Archaeological Landmark and is also listed on the National Register of Historic Places.
Fort Lancaster was established by Captain Stephen D. Carpenter and his First Infantry Regiment on August 20, 1855. The fort became a permanent fort almost exactly a year later on August 21, 1856. The soldiers built the fort structures out of limestone and adobe with grass thatched roofs and, in some cases, wooden shingles. It was the responsibility of the troop at Fort Lancaster to provide protection to travelers who were passing through on their way to California. The post was well supplied with fresh water from the Pecos River. However, because of its extremely remote location, the soldiers did not have much in the way of entertainment at Fort Lancaster; they spent their time maintaining the site and patrolling the San Antonio-El Paso Road. Due to the beginning of the Civil War, Fort Lancaster was abandoned in 1861. Not long after, the Second Regiment attempted to utilize the post defensively, but were not successful and left for good in 1862. However, Fort Lancaster got a second life when in 1867 it was used as a sub-post for the Buffalo Soldiers' 9th Calvery. According to Texas Historical Commission, In December 1867, 40 soldiers and officers held off roughly 400 Kickapoo with only three casualties. Today, Fort Lancaster remains the only Texas Army post that was attacked by Native Americans.