Mount Tambora

Mount Tambora, or Tomboro, is an active stratovolcano in West Nusa Tenggara, Indonesia. Located on Sumbawa in the Lesser Sunda Islands, it was formed by the active subduction zones beneath it. Before the 1815 eruption, its elevation reached more than 4,300 metres (14,100 feet) high, making it one of the tallest peaks in the Indonesian archipelago.

Tambora underwent a series of violent eruptions, beginning on 5 April 1815, and culminating in the largest eruption in recorded human history and the largest of the Holocene (10,000 years ago to present). The magma chamber under Tambora had been drained by previous eruptions and lay dormant for several centuries as it refilled. Volcanic activity reached a peak that year, culminating in an explosive eruption that was heard on Sumatra island, more than 2,600 kilometres (1,600 mi) away and possibly over 3,350 kilometres (2,080 mi) away in Thailand and Laos. Heavy volcanic ash rains were observed as far away as Borneo, Sulawesi, Java, and Maluku islands, and the maximum elevation of Tambora was reduced from about 4,300 to 2,850 metres (14,110 to 9,350 feet). Estimates vary, but the death toll was at least 71,000 people. The eruption contributed to global climate anomalies in the following years, while 1816 became known as the "year without a summer" because of the effect on North American and European weather. In the Northern Hemisphere, crops failed and livestock died, resulting in the worst famine of the century.