The Quadrangle at Fort Sam Houston was built beginning in 1876 to function as the post's supply depot and quartermaster storehouse complex, a working warehouse compound where the Army received, stored, and issued equipment, provisions, and materiel for troops across the region. Its landmark clock tower, added a few years later, served the practical purpose of timekeeping for the depot's operations and remains its most recognizable feature. Beyond routine logistics, the Quadrangle's grounds hold notable historical associations: in 1886 the Apache leader Geronimo was briefly held in the area following his surrender, and in the early 1910s the post served as a site for pioneering U.S. Army aviation testing and training, connecting the location to the early development of military air power. As Fort Sam Houston grew into a major Army installation, the Quadrangle's original storehouse buildings were adapted over time to administrative and ceremonial functions rather than active warehousing. Today it functions as the historic ceremonial and administrative core of the still-active post, headquarters offices ring its courtyard, and the grounds are open to public visitors, who can walk the courtyard and view the clock tower amid free-roaming peacocks kept on the grounds, making the Quadrangle simultaneously a working military headquarters area and a public heritage attraction.