One of my first, and longest "tours" was when I was about 20.

I was studying in Parma Italy when my passport was due too expire. So, rather than taking the train, I decided too ride my bicycle from Parma to Rome (with a slight pause in Bologna due to rain). Anyway, about 3 or 4 days riding down to Rome.

I got to the US Embassy after a few long days on the road, and they refused to renew my passport because I was staying in Parma which was closer to the consulate in Milano. I spent a few days riding and touring around Rome, and a few flats in Rome (old sewups), then I headed back. I estimated around 1 megameter for the ride.