Chuuk, formerly Truk, state of the Federated States of Micronesia, part of the Caroline Islands in the western Pacific Ocean. It consists of about 15 volcanic islands encircled by a coral atoll approximately 61 km (approximately 38 mi) in diameter, and outlying atolls. Most of the outlying islands are uninhabited. The total area of Chuuk state is 127 sq km (49 sq mi).
The Japanese established a naval base in Chuuk Lagoon during World War II that was bombed by the United States Navy in 1944. The sunken Japanese ships are now a popular scuba-diving attraction for tourists. The administrative center and principal island is Weno (formerly Moen).
The principle populace focal point of Chuuk State is the Chuuk Lagoon, an enormous archipelago with bumpy islands encompassed by a series of islets on a boundary reef. The two noteworthy land and logic divisions of the Chuuk Lagoon are Faichuuk, the western islands, and Namoneas, the eastern islands.