A cyclist climbs the flanks of Mount Diablo (3,849').
Mount Diablo State Park's South Gate Road, one of two main entrances to the park.
Fire roads criss-cross the slopes of Mount Diablo and serve as prime mountain biking trails.
Fire roads criss-cross the slopes of Mount Diablo and serve as prime mountain biking trails.
Looking up toward Mount DIablo's summit from Rock City.
Large sandstone rock formations rise from the landscape at Rock City in Mount Diablo State Park.
Rock City in Mount Diablo State park.
Rock City in Mount Diablo State Park.
Rock City in Mount Diablo State Park. Mount Diablo's summit can be seen in the upper right.
Coast live oak (Quercus agrifolia) and California foothill pine (Pinus sabiniana) are common trees found on Mount Diablo's slopes.
Mount Diablo State Park.
Mount Diablo State Park.
Mount Diablo State Park.
California poppy (Eschscholzia californica) in Mount Diablo State Park.
Mount Diablo State Park.
A hang-glider soars above Mount Diablo State Park with San Francisco rising in the background.
Diablo Valley Overlook.
Mount Diablo's summit (3,849').
The summit tower.
A memorial compass rose in the summit tower, Mount Diablo State Park.
North Peak (3,557') with the Sacramento River Delta in the distance.
Mount Diablo State Park.
Summit picnic area.
Coast live oaks (Quercus agrifolia) in Mount Diablo State Park.
Mount Diablo State Park.
Mount Diablo seen from the summit of Mount Tamalpais.