Horn Island was acquired for the sole purpose of becoming a
biological weapons test site for the
U.S. military. The site was established as one of several designed to assist the newly formed U.S. biological weapons program at Camp Detrick. The U.S. Army built facilities on the island for these purposes which included several buildings, roads, and a
narrow gauge railroad. including the incinerator and chimney. The foundations of some of the military buildings are still visible on the island, which is now part of the
Gulf Islands National Seashore. Additionally, the remnants of the incinerator chimney were still visible into at least the 1980s. ==Research and testing==