Three thousand years ago Bronze Age priests in Scandinavia used to cover rock faces with carvings of ships. These strange ships are one of the great riddles of Scandinavian archaeology.

Professor Sverre Marstrander of Oslo University Museum has studied them for 17 years and has re-created one: Magnus Magnusson reports on the design, building and testing at sea of this craft whose like has not been seen for 2,500 years.