(4-2007) Entrance to Fort Union National Monument
 
Three successive forts were built to protect Santa Fe Trail travelers and to serve as a major military supply depot for the Southwest, starting with the first fort in 1851
 
The second fort  served from 1861-1862, but being made of earth and wood quickly deteriorated. It was abandoned after the Confederate invasion was turned back in March 1862 at the Battle of Glorieta Pass by a force of Colorado and New Mexico volunteers and U.S. Regulars from Fort Union
 
The adobe ruins seen today are what remain from the third fort built in 1863 and abandoned in 1891, when it had outlived its usefulness

(4-2007) Overview of Fort Union

(4-2007) Company quarters

(4-2007) Post Officers' quarters