Java is one of the islands of the Greater Sunda Islands in Indonesia, bordered by the Indian Ocean to the south and the Java Sea on the north. With a population of 147.7 million or 151.8 million, Java constitutes 56.1 percent of the Indonesian population and is the world's most-populous major island. The Indonesian capital city, Jakarta, is on its northwestern coast. Much of the well-known part of Indonesian history took place on Java. It was the centre of powerful Hindu-Buddhist empires, the Islamic sultanates, and the core of the colonial Dutch East Indies. Java was also the center of the Indonesian struggle for independence during the 1930s and 1940s. Java dominates Indonesia politically, economically and culturally. Four of Indonesia's eight UNESCO world heritage sites are located in Java: Ujung Kulon National Park, Borobudur Temple, Prambanan Temple, and Sangiran Early Man Site.
Formed mostly as the result of volcanic eruptions from geologic subduction between the Sunda Plate and Australian Plate, Java is the 13th largest island in the world and the fifth largest in Indonesia by landmass at about 138,800 square kilometres.