Many researchers now believe that the first route followed was along the coast of the Indian Ocean and that water transportation was invented very early on to reach islands in Southeast Asia.
Eco transportation charted the ocean blue as well as researchers at Boston University unveiled plans for a fleet of ships that generate energy from the motion of the ocean.
The researchers said that's because of Honolulu's place in the air transportation network: in the Pacific Ocean, with many connections to distant, large, and well-connected hubs.
The same goes for train travel and car travel but there is an exception for travel by boat: if you travel by ocean liner, cruise ship, or other form of luxury water transportation for business purposes, there is a daily limit on the amount you can deduct.