Lake Toba was formed as a consequence of the largest volcanic eruption ever to occur on earth, approximately 75,000 years ago, which ejected some 1,500 to 2,000 km3 of material.

It is the largest year-round lake in Southeast Asia, is located in the province of North Sumatra, Indonesia, approximately 176 km to the west of the provincial capital, Medan.

It is the largest volcanic lake in the world.BATAK

Also spelled BATTAK, or BATTA, several closely related ethnic groups of central Sumatra, Indonesia. They possess a written language of their own, consisting of several diverse dialects, belonging to the Austronesian family. The Batak are descendants of a powerful Proto-Malayan people who until 1825 lived in relative isolation in the highlands surrounding Lake Toba in Sumatra.The Batak had felt Indian influences by the 2nd or 3rd century AD and had borrowed ideas of government, writing, elements of religion, arts, and crafts. They did not, however, develop a unified state and today are found in six cultural divisions. Within these are exogamous patrilineal clans known as marga. A price is paid for a bride, who then becomes a member of her husband's group. Among the Toba Batak a village consists of several clan houses, but in the Karo division all dwell in one or more longhouses.Ancestors, plants, animals, and inanimate objects are considered to possess souls or spirits that can be coerced or enticed by male priests. These priests are aided by female mediums who, in trance, communicate with the dead. Cannibalism was once practiced, but victims were confined to prisoners and those guilty of incest.Today most of the Toba Batak are literate, as is the case of many in the other groups. Many are Christians who occupy places of importance in trade and in the Indonesian government. Muslim missionaries have been active in regions to the north and south of the Toba. The estimated population of Batak lands is about 3,100,000, of which about one-third is Christian, one-third Muslim, and the balance still adherents of traditional beliefs.After World War II there was a mass movement of Toba squatters into the rich plantation lands of the east coast, formerly owned by foreign investors.Religion, Batak Protestant Christian Church

Also called Huria Kristen Batak Protestant (hkbp), church in northern Sumatra, Indonesia, organized as an independent church in 1930 and constituting the largest Lutheran church in Asia. It developed from the work of missionaries of the Rhenish Mission Society, established in Barmen, Ger., in 1828. Under the leadership of the German Lutheran missionary Ludwig Ingwer Nommensen, the missionaries began working among the Batak people in Sumatra in 1862. Resistance to Christianity lessened slowly, and by 1880 entire tribes and villages began converting to Christianity. Nommensen translated Luther's Small Catechism, the New Testament (1878), and several other works into the Batak language and wrote hymns and a church order for the Batak church. By 1894 the entire Bible had been translated. Education was stressed, and many elementary schools were established in the villages. A Batak mission society extended the mission work among the people.

After the HKBP was organized in 1930, the foreign missionaries began withdrawing; the last of them departed in the 1940s, during World War II and the Indonesian war for independence from The Netherlands. The HKBP was accepted as a member of the Lutheran World Federation in 1952. The central location: Samosir

Island in Danau (lake) Toba, Sumatera Utara propinsi (North Sumatra province), Sumatra, Indonesia. Approximately 200 sq mi (520 sq km) in area, the island occupies nearly half the lake and is joined to its western shore by an isthmus, at which point is the island's principal town, Pangururan. In the east, the island rises to 5,350 ft (1,630 m), but the level of the surrounding water is 2,989 ft. The mountain Dolok Pusubukit on the isthmus joining Samosir to the mainland is believed to have been the home of the first Batak, the mythical first ancestor of the Batak people, who inhabit much of Sumatera Utara. The Samosir Batak grow rice, raise cattle, fish in the lake, and raise shallots and garlic for sale. They are mainly Christian, with ancestor worship still important. The island contains many ancient megaliths; tourism is increasingly important to the eastern side of the islandÂ

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