Mt. Diablo Hog Club was built and continues to be operated by Harley Davidson enthusiasts. Club members pay modest annual dues to participate in rides and monthly meetings. Since 1988 the mission of this club has been to serve as a place for Harley Davidson enthusiasts to meet and ride with other enthusiasts. The group is alive and going strong with over 300 members, run with the help of the Harley Davidson Dealership in Walnut Creek.