The 100/200 is a one day bicycle ride that stretches from the Canadian border to the Massachusetts state line. Route 100 is widely recognized as one of Vermont's most scenic highways and the ride is routed to minimize automobile traffic. With nicely spaced town greens for breaks, numerous scenic vistas, a number of long, steep climbs, and 50 mph descents, the 100/200 is a true New England classic, and a prime target for experienced cyclists.
While not a challenge to be tackled by the casual rider, the 100/200 should be within the capabilities of most well-trained cyclists. Bicycling Magazine included this ride in a 1989 article titled "Hell On Wheels: The 10 Toughest One-Day Rides in North America." Whether you've never tried a double-century before, or you're an experienced long-distance cyclist, this ride presents you with a challenge that you will always remember!
http://100-200.org/Registration.html