Faultlines, black holes and glaciers: mapping uncharted territories

In the era of satellites and Google Maps there are still areas that remain a mystery

On a quiet summer evening, the Aurora, a 60ft cutter-rigged sloop, approaches the craggy shore of eastern Greenland, along what is known as the Forbidden Coast. Its captain, Sigurdur Jonsson, a sturdy man in his 50s, stands carefully watching his charts. The waters he is entering have been described in navigation books as among "the most difficult in Greenland; the mountains rise almost vertically from the sea to form a narrow bulwark, with rifts through which active glaciers discharge quantities of ice, while numerous off-lying islets and rocks make navigation hazardous". The sloop is single-masted, painted a cheery, cherry red. Icebergs float in ominous silence.

Where Jonsson, who goes by Captain Siggi, sails, he is one of few to have ever gone. Because the splintered fjords create thousands of miles of uninhabited coastline, there has been little effort to map this region. "It's practically uncharted," he says. "You are almost in the same position as you were 1,000 years ago."