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Fort Union National Monument contains the ruins of a 19th century military outpost along the Santa Fe Trail. It’s located in northern New Mexico near the city of Las Vegas.
Visiting
Fort Union National Monument is open daily throughout the year except Thanksgiving Day, Christmas Day, and New Year’s Day. There’s no fee to enter (as of April 2023), and there are ranger-guided programs offered almost every day.
Visitor Center
The small visitor center contains exhibits about the fort as well as a short film about the Santa Fe Trail. On display are historical items used at the fort as well as displays explaining the rugged life of soldiers on the frontier.
Trails
A 1 ¼ mile self-guided interpretive trail takes visitors through the entire fort. There’s also a shorter ½ mile trail through a smaller portion. The ruins are all from the third Fort Union (see below).
When I visited, there was a driving rain and I had to rush through as quickly as possible. I was soaked at the end and didn’t get as much out of it as I had hoped, so a return visit is definitely on the table. Because I’m missing a lot of the information I should have picked up during my walk, I’ll mix in photos with a history of the fort and rewrite this page when I have another chance to visit.
First Fort Union
The first Fort Union was built in 1851 to protect the inhabitants and travel routes of the New Mexico Territory. Its purpose was to move the territory headquarters out of Fort Marcy in Santa Fe and reorganize the defense structure. It also moved the 1,300 or so soldiers out of the 11 small outposts that were scattered in towns throughout the territory.
The fort was built as an open campus with buildings spread out over about 80 acres and looked more like a village than a military outpost. Living conditions were terrible and the soldiers participated in several campaigns against the Indians. The buildings stood until 1861, after the Civil War broke out.
Second Fort Union
The second Fort Union was built as a defensive structure and designed to withstand a siege. It took the shape of a star and was constructed in less than a year with earthen mounds. It was located about a mile east of the first Fort Union. The foundations can still be seen today.
With the Confederate Army already taking Santa Fe, Fort Union was the only obstacle in their path to the gold fields of Colorado. Soldiers stationed at the fort joined forces with the Colorado Volunteers and confronted them at the Battle of Glorieta Pass from March 26-28, 1862. They defeated the Confederates, led by Brigadier General Henry Hopkins Sibley (1816-1886), forcing them to retreat to Texas. It was one of the most important battles of the Civil War and eliminated the Confederate threat in the West. The Glorieta Pass Battlefield is now part of Pecos National Historical Park.
Third Fort Union
The third Fort Union, which is what remains today, was built in 1862. It contained several buildings made out of clay, stone, and lumber. The buildings were made of adobe bricks and sat on stone foundations.
The third Fort Union housed both cavalry and infantry. It also employed several civilians at its huge supply depot. The fort served as the headquarters of the 8th Cavalry in the early 1870s and the 9th Cavalry in the late 1870s, participating in the Apache Wars.
When the Atchison, Topeka and Santa Fe Railway arrived in 1879, the Santa Fe Trail diminished in importance, and so did Fort Union. The fort was abandoned in 1891 and fell into ruins.
Fort Union National Monument was founded on June 28, 1954, in order to preserve the ruins and the important historic role they played.
