I finished a year of graduate work at Oregon State, and decided to ride my bike back home to New England. Threw away a massive amount of stuff, packed the rest in UPS and sent it home. Hopped on my bike June 1st and got to New England at foliage time early October, following the trans-Am trail with "Side trips" to Jasper Alberta, and North Carolina to pick up the Blue Ridge Parkway.
Was hooked, and did about 20 other tours, including a world tour, over the next few decades.