Mount Diablo State Park: Donner Canyon to the Falls Trail Professional Review and Guide
"While creeks running down Mount Diablo may dry in summer, the reality is that there are always cool canyons, and even on hot days, cool breezes cross upper elevations on the less-traveled north side of the mountain. Because the trails here are protected from the sun most of the day, Donner, Back, and Mitchell Canyons have among California’s best wildflower shows. The seasonal waterfalls in the upper reaches of Donner Canyon, especially in Wild Oat Canyon along the Falls Trail, are spectacular. Trails Surface: Double-track, dirt trail; narrow, single-track trail with some rocks to traverse."