Obelisk at Ground Zero, Trinity Test Site, on the White Sands Missile Range, New Mexico, United States. This is the site of the world's first atomic explosion on 16th July 1945. The atomic bomb was developed by the Manhattan Project, a collaboration during World War II by the United States, United Kingdom, Canada, and European physicists, to develop the first nuclear weapons. The second atomic bomb was dropped on Hiroshima, Japan, on 6th August and the third on Nagasaki, Japan, on 9th August. On 14th August 1945, Japan surrendered, ending World War II.