It would be impossible to do without taking breaks, as explained in the article:

> Due to visa limits, Bushby has had to break up his walk. In Europe, he can stay for only 90 days before leaving for 90, so he flies to Mexico to rest and then returns to resume the route.

Given that he literally swam across the Caspian Sea in order to avoid Russia and Iran because of legal issues, nevermind bring imprisoned in Russia due to what sounded like bureaucratic BS, it's more impressive than I first thought.