Hekla (ˈhɛhkla), or Hecla, is an active stratovolcano in the south of Iceland with a height of . Hekla is one of Iceland's most active volcanoes; over 20 eruptions have occurred in and around the volcano since the year 1210. During the Middle Ages, the Icelandic Norse called the volcano the "Gateway to Hell" and the idea spread over much of Europe.
Hekla is part of a volcanic ridge, long. The most active part of this ridge, a fissure about long named Heklugjá ˈhɛhklʏˌcauː, is considered to be within Hekla proper. Hekla looks rather like an overturned boat, with its keel being a series of craters, two of which are generally the most active.
The volcano's frequent large eruptions have covered much of Iceland with tephra, and these layers can be used to date eruptions of Iceland's other volcanoes. Approximately 10% of the tephra created in Iceland in the last thousand years has come from Hekla, amounting to 5 km3. Cumulatively, the volcano has produced one of