Rowing like Vikings in the name of science
16 July 2012 Last updated at 14:13 BST
A Viking museum in the German town of Busdorf has welcomed the largest reconstruction of a medieval long-ship, the Havhingsten, or Sea Stallion.
30 metres long and using only the technology available a thousand years ago, it sailed from Denmark to participate in a festival of square rigged ships.
The gruelling experience of its crew of 60 allowed experts to gain insights into the life of Viking seamen.
Tom Donkin reports.