The Nuclear Weapon Archive
Today in 1957, a nuclear bomb was detonated underground in Nevada - the first underground nuclear test in history. It occurred at the Nevada Test Site, north of Las Vegas. The weapon was a 1.7 kiloton nuclear warhead. The bomb, code named "Rainier," was fully contained and did not result in any known radioactive fallout.
Rainier was one of 29 nuclear tests, known as Operation Plumbbob. Plumbbob was completed on October 7, 1957.
The test was the result of the Manhattan Project, first authorized by FDR in December of 1941. The first above-ground nuclear test happened at the Trinity site in New Mexico, on July 16, 1945. It was only a few weeks before he dropped the bomb on Hiroshima and then Nagasaki a few days later. All told, an estimated 200,000 people were killed in the bombings. Japan is still coping with the consequences of the bombings all these decades later.
Operation Plumbbob came at the height of the Cold War. Above-ground nuclear testing would come to be outlawed entirely in 1963, with the passage of the Limited Test Ban Treaty. Nuclear tests would have to be conducted underground - no detonations were permitted in the atmosphere, underwater or in space.
There have been a significant number of nuclear tests conducted at the Nevada Test Site. There have been 928 documented detonations, between 1951 and 1992. Nuclear testing was outlawed whole cloth in 1996, when the US passed the Comprehensive Test Ban Treaty.