I have just got back from a trip through Europe and Asia with my Range Rover and while in Mongolia I met a guy who was doing a round the world trip using Human power only.
He has completed the first leg of the trip which was from Anchorage to Ulaan Baatar across the Bearing Straite in winter by towing a sledge and swimmig the parts that were not frozen.
he can walk ,swim ride a bicycle and row but not use wind power or any form of mechanical power like ferries or sail boats.he also has to cross the equator twice.
The web site id Nexus Epeditions where his blog is