Nuclear test sites are locations where governments have tested nuclear weapons. Governments that have tested nuclear weapons include the United States, Russia, the United Kingdom, France, China, India, Pakistan, North Korea, South Africa, and probably Israel. The first nuclear test sites were locations in the deserts of New Mexico and Nevada in the United States. The first ever nuclear weapon, Trinity, was detonated 16 July 1945 at Alamogordo, near Socorro, New Mexico, on what is now White Sands Missile Range.
After the Allies won WWII, nuclear testing was continued by the United States during Operation Crossroads, in which two nuclear weapons, Baker and Able, were detonated at sea at Bikini Atoll in the Pacific. These were the fourth and fifth nuclear explosions on the planet, respectively, the third and fourth being the destruction of Hiroshima and Nagasaki. The explosions were used to test the effects of nuclear explosions on ships and accompanying dummies.
The energy generated by the explosions were so intense that the sea floor was reduced to a sand so fine that crabs could not climb along it without slipping to the bottom of the submarine crater. 167 natives of Bikini Atoll were moved 128 miles east to the uninhabited Rongerik Atoll, where they remain to this day, receiving little support from the US government in their wishes to return to their ancestral home.
In 1951, the United States added the Nevada Proving Grounds, now known as the Nevada Test Site, a location about 65 miles (105 km) outside of Las Vegas, Nevada, to its list of nuclear test sites. Between 1951 and 1992, there were 928 known nuclear tests at Nevada Test Site, with 828 of these being underground. Most of the iconic images of nuclear explosions come from these numerous tests.
Between 1946 and 1961, various sites in the Marshall Islands, Bikini Atoll being the first and most famous, were used as nuclear test sites, collectively known as the Pacific Proving Grounds. This site was the most popular of the atmospheric nuclear test sites -- over 105 bombs were detonated high in the atmosphere in the area -- including the bombs with the highest yield, which must be detonated at high altitudes to minimize fallout. The United States's most powerful nuclear test, Castle Bravo, with a yield of 15 megatons, was conducted in this region.