A challenging double-century that began in 1984, the 100/200 (a.k.a. 200-on-100) spans Vermont, north to south, following scenic Route 100. The first 100 miles roll by fairly quickly, but save your reserves, as the climbs start in the second half of the ride, culminating in the 12-mile Mt. Snow climb.  When you finish, you'll truly understand why so many cyclists say "Vermont ain't flat!" Register at http://100-200.org