Krafla* includes one of the two best-known Víti craters of Iceland (the other is in Askja). The Icelandic word "víti" means "hell". In former times, people often believed hell to be under volcanoes. The crater Víti has a green lake inside of it.
*Krafla is a caldera of about 10 km in diameter with a 90 km long fissure zone, in the north of Iceland in the Mývatn region. Its highest peak reaches up to 818 m and it is 2 km in depth. There have been 29 reported eruptions in recorded history.
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