The Sierra Century offers four routes for the seasoned cyclist that start/end at the Amador County Fairgrounds in Plymouth: Half Metric (35 miles, 1400 ft. elevation gain) goes to Ione and loops back to Plymouth. This route is new this year. Metric (65 miles, 4500 ft. elevation gain) follows the Half Metric route to Ione and continues on to Sutter Creek, Volcano, Daffodil Hill, and Fiddletown. Century (102 miles, 7400 ft. elevation gain) follows the Metric route to Fiddletown and continues up to Mt. Aukum, Fair Play, and Slug Gulch before returning to Plymouth through the Shenandoah Valley. Double Metric (122 miles, 10,000 ft. elevation gain) follows the Century route to the top of Slug Gulch and adds an extra loop with additional climbing before returning to Plymouth. All rides are fully supported by rest and water stops, SAG vehicles with HAM radio communication, bicycle mechanics , flaggers, law enforcement personnel, and a large corps of volunteers.  http://sacwheelmen.org/sierracentury.org