Palau (/pəˈlaʊ/), historically Belau, Palaos, or Pelew), officially the Republic of Palau (Palauan: Beluu er a Belau), is an island country located in the western Pacific Ocean. The country contains approximately 340 islands, and together with parts of the Federated States of Micronesia, forms the western chain of the Caroline Islands. Its area is 466 square kilometers (180 sq mi). The most populous island is Koror. The capital Ngerulmud is located on the nearby island of Babeldaob, in Melekeok State. Palau shares maritime boundaries with the Philippines, Indonesia, and Micronesia.