Enewetak Atoll is a large coral atoll of 40 islands in the Pacific Ocean and with its 664 people (as of 2011) forms a legislative district of the Ralik Chain of the Marshall Islands. With a land area total less than 5.85 square kilometers (2.26 sq mi), it is no higher than 5 meters and surrounds a deep central lagoon, 80 kilometers (50 mi) in circumference. It is the second-westernmost atoll of the Ralik Chain and is 305 kilometers (190 mi) west from Bikini Atoll.

It was held by the Japanese from 1914 until its capture by the United States in February 1944, during World War II. Nuclear testing by the US totaling more than 30 megatons of TNT took place during the cold war; in 1977–1980, a concrete dome (the Runit Dome) was built on Runit Island to deposit radioactive soil and debris.

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