Sumatra sometime also being spelled Sumatera, it is the sixth largest island in the world and is the largest island entirely in Indonesia. Sumatra is not very densely populated. It is nonetheless the fourth most populous island in the world. The most populous regions include most of North Sumatra and central highlands in West Sumatra, while the major urban centers are Medan and Palembang. The people composed of many different ethnic groups, speaking 52 different languages. Most of these groups, however, share many similar traditions and the different tongues are closely related. Malay-speaking people dominate the eastern coast, while people in the southern and central interior speak languages related to Malay, such as the Lampung and Minangkabau people. The highland of northern Sumatra is inhabited by the Bataks, while the northernmost coast is dominated by Acehs. Ethnic Chinese minorities are also present in urban centers. A majority of people in Sumatra are Muslims (90%). Most central Bataks, meanwhile, are Protestant Christians where a religion introduced by the Dutch. The rest follow Hinduism, Buddhism, Catholicism, and Chinese traditional beliefs.
The longest axis of the island runs approximately 1,790 km northwest to southeast, crossing the equator near the center. At its widest point the island spans 435 km (270 miles). The interior of the island is dominated by two geographical regions, whereby the Barisan Mountains in the west and swampy plains in the east. To the southeast is Java, seperated by the Sunda Strait. To the north is the Peninsula of Malaysia, seperated by the Straits of Malacca. To the east is Borneo where Sabah, Sarawak & Brunei are, across the Karimata Strait. West of the island is the Indian Ocean.
The backbone of the island is the Barisan mountains chain, with the active volcano Mount Kerinci's 3,805 m (12,467 ft) the highest point, located at about the midpoint of the range. The volcanic activity of this region endowed the region with fertile land and beautiful sceneries, for instance around the Danau Toba (Lake Toba). It also contains deposits of coal and gold.
