Trinity was the code name of the first detonation of a nuclear weapon, conducted by the United States Army on July 16, 1945, as part of the Manhattan Project. The test was conducted in the Jornada del Muerto desert about southeast of Socorro, New Mexico on what was then the USAAF Alamogordo Bombing and Gunnery Range (now part of White Sands Missile Range). The only structures originally in the vicinity were the McDonald Ranch House and its ancillary buildings, which scientists used as a laboratory for testing bomb components. A base camp was constructed, and there were 425 people present on the weekend of the test.