43rd Mount Diablo Challenge - Early Bird Pricing ends August 31
Registration is open for the 43rd Annual Mount Diablo Challenge being held on Sunday, Oct 4, 2026 and this is your reminder to secure early-bird pricing before it ends on August 31. Prices will go up on September 1.
Join over 950 cyclists in tackling the 11.2 mile, individually timed, car-free climb to the 3,249 feet summit of Mt. Diablo. The event is open to all ages, abilities and bike types - including road, mountain, tandem, elliptical, unicycles and e-assist. The road to the summit is closed to vehicles for the event. From the summit, riders will descend in groups behind escort cars.
Celebrate afterward with free food, music, prizes and a vendor expo.
Visit the event website for more information or click here to secure your spot. If you know of anyone interested in volunteering for the event, there are several volunteer roles still open.
The event is organized by the Valley Spokesmen Bicycling Club.