Kadavu, with an area of 411 square kilometers, is the fourth largest island in Fiji, and the largest island in the Kadavu Group, a volcanic archipelago consisting of Kadavu, Ono, Galoa and a number of smaller islands in the Great Astrolabe Reef. Its main administrative centre is Vunisea, which has an airport, a high school, a hospital, and a government station, on the Namalata Isthmus where the island is almost cut in two. Suva, Fiji's capital, lies 88 kilometers to the north of Kadavu. The population of the island province was 10,167 at the most recent census in 2007.
Kadavu is one of Fiji's fourteen Provinces, and forms part of the Eastern Division, which also includes the Provinces of Lau, Lomaiviti and Rotuma. Kadavu also belongs to the Burebasaga Confederacy, a hierarchy of chiefs from southern and western Fiji.
The island is 93 kilometers long, with a width varying from 365 meters to 13 kilometers. The island is almost sliced in two at the narrow Namalata Isthmus, which separates Namalata Bay on the northern coast from Galoa Harbour on the southern coast. Within Galoa Harbour lie Galoa Island and the tiny islet of Tawadromu. Kadavu is characterized by its rugged and mountainous terrain. The tallest mountain is Nabukelevu, also known as Mount Washington, which stands at 822 meters high, on the western end of the island.