Colonia is an urban area belonging to the municipalities of Rull and Weloy, which serves as the capital of the State of Yap, one of the Federated States of Micronesia. It administers both Yap proper and some 13 atolls and islands reaching to the east and south for some 800 km (500 mi).
The 2010 Census population was 3,126.
A Spanish Catholic mission was established in Colonia in 1885, during Yap's time as a colony of Spain. The Immaculate Heart of Mary Cathedral, seat of the Diocese of Caroline Islands, is located in Colonia.
Tomil Harbor is the main port of Yap State. Ships have to travel through a 1.5 miles (2.4 km) long reef-bordered passageway to reach the port, where there is a 230 feet (70 m) long small craft wharf.
Coordinates: 9°31′N 138°08′E / 9.517°N 138.133°E