Chuuk Lagoon, also known as Truk Lagoon, is a sheltered body of water in the central Pacific. The atoll consists of a protective reef enclosing a natural harbour. Chuuk Lagoon is part of the larger Caroline Islands group. The area consists of eleven major islands and forty-six smaller ones within the lagoon, plus forty-one on the fringing coral reef, and is known today as the Chuuk islands, part of the Federated States of Micronesia in the Pacific Ocean.