As part of the Manhattan Project, the world's first atomic bomb was safely detonated on July 16, 1945, at 5:29 a.m. Mountain War Time, at the Alamogordo Bombing Range in New Mexico. The "Trinity" test was a critical milestone in the development of the atomic bomb, opening the way for its eventual use in World War II. The explosion produced a massive amount of energy, resulting in a mushroom cloud visible for kilometres around.