Summit Trail

Summit Trail ascends to the 3,849-foot peak of Mount Diablo, a mountain renowned for its extraordinary viewshed that some geographers claim surpasses every other peak on Earth except Kilimanjaro in terms of the total land area visible from its summit on a clear day. Rising in dramatic isolation from the surrounding East Bay terrain, Mount Diablo commands panoramic views extending from the Sierra Nevada to the Farallon Islands, from Mount Shasta to the Tehachapi Mountains. The summit trail climbs relentlessly through successive vegetation zones, passing through oak woodland, chaparral, and rocky summit terrain that shifts dramatically with season and elevation. Spring brings an explosion of wildflowers including brodeia, owl clover, and California poppies that paint the hillsides brilliant orange and purple. The summit itself is capped by a stone summit building and observatory that houses interpretive exhibits explaining the remarkable geology and natural history of this isolated volcanic and serpentine mountain. Rock Creek and the network of canyons below the summit support diverse wildlife including golden eagles, prairie falcons, bobcats, and tule elk. The sustained 3,000-foot elevation gain makes this a genuinely demanding hike that rewards determined hikers with one of the most spectacular views available anywhere in the Bay Area. Water and snacks are essential for this exposed climb.