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Johnston Atoll
A former nuclear test and chemical weapons site in the Pacific
Johnston Atoll, about 750 nautical miles southwest of the island of Hawaii, has one of the darkest histories of any American island. Claimed in 1858 for its guano and made a federal bird refuge in 1926, it was later taken over by the military, which enlarged its main island and built two more from dredged coral. Rockets launched from the atoll in 1958 and 1962 carried nuclear warheads high above the Pacific, including the 1962 Starfish Prime blast that knocked out streetlights in Hawaii.
From 1971 the atoll stored chemical weapons, many moved from Okinawa, along with Agent Orange from the Vietnam War. A purpose-built incinerator destroyed the chemical stockpile between 1990 and 2000, and the last official flight left in 2004 after cleanup. Johnston is now an uninhabited wildlife refuge, visited mainly by small field teams who spent years eradicating an invasion of yellow crazy ants, a job declared complete in 2021.