Fort Marcy, Military fort in Santa Fe, United States.

Fort Marcy was a military reservation on a flat-topped hill about 650 yards northeast of Santa Fe's plaza. Workers and troops built an irregular tridecagon of adobe walls 9 feet high and 5 feet thick, with an adobe blockhouse and powder magazine outside the defense. No garrison stood inside the fort; limited quarters were built on the outside mesa.

In August 1846 General Stephen W. Kearny's Army of the West occupied Santa Fe, and the next day Kearny had engineers William Emory and Jeremy Gilmer stake out a fort on a flat-topped hill 650 yards northeast of the plaza. President Andrew Johnson ordered it abandoned on August 28, 1868, and the government sold the site at auction in 1891.

The fort's name honors William L. Marcy, Secretary of War under President Polk when General Kearny ordered the post built in 1846. In 1887, a visitor from Silver City, Tassie Wilson, found Spanish coins hidden in the old walls, some dated 1726 and 1740; the ensuing dig by Santa Fe residents destroyed what remained of the walls.

The site is part of Old Fort Marcy Park and can be reached on foot from the main plaza in about 10 to 15 minutes by walking northeast. The path goes uphill but is easy to follow, and signs at the site explain what visitors are looking at.

Despite being built on a commanding hilltop, the fort was never used in actual combat during its entire time of operation. It functioned more as a symbol of American presence in the territory than as a defensive position that saw fighting.