Mount Diablo is a mountain of the Diablo Range, in Contra Costa County of the eastern San Francisco Bay Area in Northern California. It is south of Clayton and northeast of Danville. It is an isolated upthrust peak of 3,849 feet, visible from most of the San Francisco Bay Area
As mountains go, Mount Diablo isn’t particularly tall – only 3,849 feet. However, it is surrounded by low, rolling hills and broad, flat valleys, so the view from the Summit is remarkable. When conditions are best, you can see almost 200 miles. Summer days are sometimes hazy, and the best viewing is often on the day after a winter storm.