Archaeologist Greer Jarrett at Lund University in Sweden has been sailing in the footsteps of Vikings for three years. He can now show that the Vikings sailed farther away from Scandinavia, and took routes farther from land, than was previously believed to have been possible. In his latest study, he has found evidence of a decentralised network of ports, located on islands and peninsulas, which probably played a central role in trade and travel in the Viking era.