Are three volcanoes in Iceland, seemingly separate aboveground, somehow linked? How might the eruption of one affect another? Geologist Freysteinn Sigmundsson and his team descend into the crater of a dormant volcano to find out, in this video from NOVA: Doomsday Volcanoes. Experience the sights inside a volcanic chamber and learn how clues from fissures within help scientists piece together the story of how Iceland’s potent volcanoes are connected.

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