Hekla volcano are one of the most active volcanoes in Iceland. In the Middle Ages, Icelanders called it the gateway to hell.
Hekla is located on the southern edge of East African Rift zone. Unlike most of Iceland's volcanoes, which produce tholeitic basalt, the main product Hekla eruptions are basaltic andesites. Ongoing eruption of 5.5 km long crack Heklugjá, which crosses the volcano and run along the cracks.
(° source Wikipedia)