Fort Hamilton Army Base is a United States Army installation located in Brooklyn, New York. Established in 1825, it serves as a key military post and is the oldest active military installation in the New York City area. The base provides support for various military operations and houses several units, including the U.S. Army Reserve and the Army Corps of Engineers. The base is strategically positioned near the entrance to New York Harbor, making it significant for coastal defense. It also features historical structures, such as the Fort Hamilton Historic District, which showcases its long-standing military heritage and architectural significance.