This 1903 armory was described as "an unusual wood-frame building," and was one of the few armories built in the South due to lack of funds following the Civil War (1861-1865). The Italianate-style, Key West Armory incorporates an arched entrance, twin, six-sided pointed turrets, a tall parapet as well as towers and cupolas. Key West was an important Union Base during the Civil War. Volunteer troops that helped defend Key West from the Confederates were known as the Key West Rifles and then, in 1888 as the Island City Guards. The Armory was built for their descendants, the Monroe County Militia/438th Company Florida National Guard. It housed these troops and their armament. The Armory served as a training facility in World Wars I and II and later became a community center. Monroe County contracted John T. and A. Bruce Sawyer to build the Armory in 1902, as designed by T.F. Russell. The State of Florida later refunded the money, which was used to build County Road, now known as Flagler Avenue. Restoration efforts began in the 1970s prior to the building's lease to Monroe County. Management of the state-owned armory was turned over to the Historic Florida Keys Preservation Board in 1994.