Sumatra is the largest island entirely in Indonesia and ranks as the sixth-largest island in the world by area. It lies between the Indian Ocean and the South China Sea, with the Strait of Malacca to the northwest, the Sunda Strait to the south, and the Java Sea to the southeast.
Sumatra stretches for approximately 1,790 kilometers from northwest to southeast, with a maximum width of about 435 kilometers. It encompasses a land area of 473,481 square kilometers. The island is dominated by the Barisan Mountains, which run the length of the island along its western edge. These mountains are part of the Sunda Arc, a volcanic arc, resulting in several active volcanoes including Mount Krakatoa, famous for its catastrophic eruption in 1883.
The history of Sumatra dates back to ancient times with the existence of the Srivijaya Empire in the 7th to 13th centuries, which was a significant maritime power in Southeast Asia, controlling the trade routes through the Strait of Malacca. After the decline of Srivijaya, various kingdoms rose, like the Kingdom of Demak and the Aceh Sultanate, which became a center for Islamic scholarship and trade.
In the late 19th century, Dutch colonial rule was established over Sumatra following the Padri War and the Aceh War, which lasted from 1873 to 1903. After Indonesian independence in 1945, Sumatra has remained a key part of the Indonesian state, though it has seen separatist movements, notably the Aceh insurgency which was resolved in 2005 with the signing of the Helsinki Agreement.
Sumatra is known for its rich cultural diversity with numerous ethnic groups including the Batak, Minangkabau, Acehnese, and Malay peoples, each with distinct traditions, languages, and customs. The traditional dances and music of Sumatra, like the Gending Sriwijaya, reflect its historical and cultural depth.
The economy of Sumatra is largely based on agriculture, with palm oil, rubber, coffee, tea, and tobacco being major crops. The island is also rich in natural resources like coal, gold, and oil, making it a significant contributor to Indonesia's economy. However, this exploitation has led to environmental concerns, particularly deforestation and habitat loss for species like the Sumatran orangutan.
Sumatra's tropical rainforests are part of the Sunda Shelf and are home to some of the world's most endangered species including the Sumatran tiger, Sumatran rhinoceros, and Sumatran elephant. Conservation efforts are ongoing to protect these species, with areas like the Gunung Leuser National Park designated as UNESCO World Heritage Sites.