Coyote Valley Open Space Reserve is a nice park near Morgan Hill, and just 30 minutes or so from downtown San Jose (with good traffic). The preserve opened in June 2015 and features a 4-mile loop for hikers, bikers, and horse riders. Despite the relatively short total length of the trail, its hilly nature makes up in climbs for what it lacks in distance.
Event start at 8:00 for all distances.