The Northern Mariana Islands (Commonwealth of the Northern Mariana Islands) is a Commonwealth in political union with the United States of America, with capital Garapan, on the island of Saipan, which includes all the Mariana islands with the exception of the island of Guam (which is an unincorporated territory of the United States). The Mariana Islands are located to the north of the equator, in the western Pacific Ocean, east of the Philippines, south of Japan and north of the Caroline Islands, the archipelago is composed of 14 volcanic and coraline islands, the main islands are: Saipan (116 sq km), Tinian (101 sq km), Rota (85 sq km), Pagan (48 sq km), Agrihan (43 sq. km) and Anatahan (31 sq km). The southern islands of Rota, Aguijan, Tinian and Saipan are largely limestone islands of coral origin, while the northern islands (Farallon de Pajaros (Uracas), Maug, Asuncion, Agrihan (Agrigan), Pagan, Alamagan, Guguan, Sarigan, Anatahan), are volcanic and still have volcanic events, with active volcanoes on the islands of Anatahan, Pagan and Agrihan. The volcano on the island of Agrihan is the highest point of the archipelago (965 metres). The islands are located along the Mariana Trench, the deepest oceanic trench, but the deepest point, Challenger Deep (-10 911 meters), is located in the maritime area of Federated States of Micronesia, south-west of Guam. The main economic resource of Marianne is tourism, less important are agriculture (coconut palms, bananas, sugar cane, pineapple, rice) and fishing.