Journey into an Icelandic volcano
Dr Freysteinn Sigmundsson, a geophysicist at the University of Iceland and a co-leader of the FutureVolc project shows the BBC's Neil Bowdler around the dormant Thrihnukagigur volcano in Iceland.
They head down into the volcano on a cradle and see the magma-filled crack where magma forced its way up through the Earth's crust 5000 years ago, carving out a unique volcanic chamber.