Ranks of chimneys 8 miles northwest of Watrous on Hwy 161 are stark reminders of the days when Fort Union was the largest military post on the Southwest frontier. Fort Union was the chief quartermaster depot 1851-1891 for nearly 50 forts throughout the region, as well as the primary station for troops assigned to protect settlers and Santa Fe
Trail travelers. The site was well chosen, for the branches of the Santa Fe Trail - the Mountain Branch and the Cimarron Cutoff - converged about 6 miles south. In addition, the remote location put the soldiers closer to the tribes and farther from Santa Fe, then considered "a sink of vice and extravagance."
A 1.25 mile tour trail explores 100 acres of adobe ruins. A visitor center with a museum relates fort history. Daily during the summer, people in period clothing demonstrate aspects of fort life.