The development of navigation is reflected in the shipfinds, worldwide and Nordic.
Perhaps the world's oldest case of documented navigation is the legend of Noah, the Deluge and the Ark. The origin of this story goes back beyond the Bible. It is told in the Gilgamesh Epic and you can read an article on Wikipedia.
Unsolved riddle: Latvia's main river the Daugava leads towards the Dnepr River, Kiev and the Black Sea. This was an old shipping route for Vikings and others. Along the Daugava there are hill forts spaced at about a daytrip's distance. Why? The underwater parts of these hill forts have never been excavated.
Related documents may be found under History of Shipbuilding or Viking and Nautical links. There is plenty of more info on the web about ancient and medieval seafaring, from the Argonauts and the Odyssey to the Hanseatic league. Use a search engine with those keywords and you will find.
page by Per Åkesson, rev jul '12