The Rock y Road 50/50 Race will be held in Tucson, Arizona on Saturday, October 20th, 2007 at 6:00am at McDonald Park, 4100 N Harrison Rd, Tucson, AZ. This is an endurance race for those wanting to test their limits. It has 100 miles with 12,134 feet of climbing. There are two sections of the course, a 50 mile mountain bike loop and a 50 mile road bike loop, both will be completed in succession.

For more information, please visit the Arizona Endurance Series.