More info: http://www.greatdivideroute.com

Great Divide Mountain Bike Route (GDMBR) description from Wikipedia:

Following the Continental Divide as closely as practicable and crossing it 30 times, about 90% of the GDMBR is on unpaved roads and trails and requires basic off-pavement riding skills to complete. The unpaved portions of the route range from high quality dirt or gravel roads to a few short sections of unmaintained trails which may not be possible for most people to ride at all. 

The GDMBR has over 200,000 feet (60,960 meters) of elevation gain and loss for the rider to contend with.[4] While most of the GDMBR is off the pavement, the route does not require highly technical mountain bike riding skills. The route has been designed to provide a riding experience primarily on very low trafficked roads through mostly undeveloped areas of the Rocky Mountain west.

The GDMBR is routed through a variety of terrain and geographic features. Highlights include the Flathead Valley in British Columbia; Grand Teton National Park and the Great Divide Basin in Wyoming; South Park and Boreas Pass in Colorado; and Polvadera Mesa and the Gila Wilderness in New Mexico. Colorado's Indiana Pass, at 11,913 feet (3630 meters), is the highest point on the route. On route, the rider will encounter isolated river valleys, mountain forests, wide open grasslands, high desert, and, near the end of the ride, a section of the Chihuahuan Desert. The GDMBR passes though some larger towns, including Helena and Butte, Montana; Pinedale and Rawlins, Wyoming; Steamboat Springs, Breckenridge, Salida, and Del Norte, Colorado; and Grants and Silver City, New Mexico. Otherwise, only extremely small towns will be encountered, limiting the variety of goods and services available to riders. Antelope Wells, New Mexico is the most commonly known starting or finishing point of the Continental Divide trail, but due to its remote location devoid of any lodging or services, Columbus, New Mexico, is an alternate starting or finishing point for those hiking or biking the Continental Divide trail.[5] Located 3 miles from the International Port of Entry at Palomas, Mexico, Columbus is a small border village with such amenities as two modest hotels, a gas station, a handful of small cafes, a post office, bank, mechanics, and groceries.