Yap is the westernized name of Wa'ab, an island in the Caroline Islands of the western Pacific Ocean. Colonia is the capital of Yap State of the Federated States of Micronesia. Yap island proper actually made up of three islands, the others being Map and Rumung. The three are close together though separated by water and are surrounded by a common coral reef and are formed from an uplift of the Philippine Sea Plate referred to as high islands as opposed to atolls. The land is mostly rolling hills densely vegetated. Mangrove swamps line much of the shore. Yap's indigenous cultures and traditions are strong compared to other states in Micronesia. Colonia is the capital of the State of Yap which includes Yap proper and the fourteen outer islands fourteen reaching to the east and south for some 800 km (500 mi), namely Eauripik, Elato, Fais, Faraulep, Gaferut, Ifalik, Lamotrek, Ngulu, Olimarao, Piagailoe (West Fayu), Pikelot, Sorol, Ulithi, and Woleai atolls, as well as the island of Satawal (see map). Historically a tributary system existed between the outer islands, mostly atolls, and Yap proper a high (volcanic) island. This probably related to the need for goods from the high islands including food and wood for construction of seagoing vessels. The state has a total land area of 102 km2 (39 sq mi).