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Fort Union Site History

Historic View
A view looking southwest at the Officer's Quarters as it appeared in the 1870's
Image source: Arrott Fort Union Collection at the Special Collections & University Archives, New Mexico Highlands University.
The Remains of Fort Union
 The adobe walls of Fort Union stand at all heights, some leaning and twisted, others with only the foundations defining former buildings, and brick chimneys dramatically rising above the walls. Rectangular voids in the adobe walls once served as doors and windows and some are framed by wooden lintels. Today, there are no roofs, to shelter and protect exposed walls from the elements.
A view looking north down the  line of the Officer's Row as it appears today.

Between 1851-1891, the fort functioned as an active military depot and was the largest military post west of the Mississippi. Situated on the Santa Fe Trail, the ruts of the wagons are still visible today; Fort Union earned the reputation as the “guardian of the Santa Fe Trail.”  Fort Union was constructed in three phases: the First Fort (1851), the Second or Star Fort (1861, demolished 1866) and the Third Fort (1863-1868). Today, the Third Fort is the most actively interpreted of the three by the National Park Service and is open to visitors.

Historic View
The Mechanic's Corral during the period when the fort was still an active military outpost.
Image source: Arrott Fort Union Collection at the Special Collections & University Archives, New Mexico Highlands University.
The Third Fort
The third iteration of Fort Union was more architecturally sophisticated than its predecessors with an organized grid plan and Territorial Style buildings of adobe walls, stone foundations, and brick chimneys. In 1891, Fort Union was abandoned. By the end of the 19th century, with the end of the Indian wars and the arrival of the railroad, there was no longer a need for the Santa Fe Trail nor the military posts like Fort Union that had defended it.  After the fort was abandoned in 1891, it was set upon by locals who removed woodwork and other valuables and the adobe walls were left to weather and deteriorate. All earthen sites are extremely vulnerable to moisture and their deterioration will quickly advance as a result of missing architectural elements such as roofs. Fort Union National Monument is no exceptio, its archaeological, architectural and cultural landscape evolving over time to both weather and preservation. 

Established in 1964, Fort Union National Monument, New Mexico, is the largest earthen ruin in North America, and commemorates the United States’ expansion of the American frontier during the age of Manifest Destiny.
Conservation Efforts
Efforts to conserve Fort Union National Monument began with its stabilization in 1956 following its  inscription as a National Monument two years prior. Founding legislation for Fort Union mandates that the site be preserved as a "stabilized ruin".  Early preservation efforts conducted between 1956 and 1961 included excavation, stabilization of the adobe walls, cisterns and chimneys, the insertion of wall bracing and rebuilding of corners and window openings supporting wooden lintels. In keeping with the original mandate, only a small number of leaning walls were straightened.

The practice of shelter coating the adobe walls as a maintenance technique began in 1963. Amended soil-cement mixtures and applied chemical consolidants were used until the 1980s when the park service reverted to using more traditional unamended methods of adobe conservation.

Earthen shelter coats, which have proven to be effective protection for the original adobe, continue to be employed at the monument. In 2016, in partnership with the Vanishing Treasures Program, the park staff at Fort Union conducted a successful straightening of a leaning wall at the Hospital building. While the process was effective it was apparent that it would not be a viable option for all leaning walls at the park, due to high costs.
Mechanic's Corral
A view of the Mechanics Corral and Depot buildings looking  north.

A view of the historic sundial with the Mechanics Corral in the distance.
Modern pano