Thursday, October 26, 2017
Diablo Foothills is an imposing gateway to the beautiful parklands of Mt Diablo State Park and Walnut Creek Open Space. The Foothills 1,060 acres are valued for their striking geologic formations, their sweeping panoramas of the San Francisco Bay Region and the rural quality of the adjacent rolling grasslands.
This hike goes for a counter-clockwise loop from Castle Rock Trailhead up to Shell Ridge, down to Twin Ponds and back up to the ridge on Hanging Valley Trail. The route includes a beautiful descent along Buckeye Ravine and a return on Stage Rd through Pine Canyon.
Head south on Castle Rock Trail from the Diablo Foothills Trailhead parking lot, it goes south along the eastern edge of the park with views of the Castle Rock Rec Area.
At the Castle Rock Single Track Trail junction, go left to stay on Castle Rock, it continues southward to the next trail junction.
Go straight onto Stage Rd, the fire road rises up from the canyon floor to the next junction at Fairy Lantern Trail.
Turn right onto Fairy Lantern, the road moderately winds up through the oak woodland to the next junction at Shell Ridge Trail.
Go right onto Shell Ridge, the trail continues uphill through the oak woodland to the next trail split.
At the Shell Ridge Loop Trail junction, go right onto the Loop Trail, it moderately climbs westward through the scattered oaks towards Shell Ridge.
At the next trail junction, go left to stay on Shell Ridge Loop Trail, it turns southward as is continues up to the top of the ridge.
The trail drops downhill along the park boundary with gorgeous views of Mt Diablo and the surrounding rolling hills. Enjoy the panoramic views!
At the “Please stay on Trail” sign, turn right and follow the cattle trail downhill onto the Briones Mt Diablo Trail.
Turn right onto Briones Mt Diablo Trail, it leads to the trail gate into Walnut Creek Open Space.
The trail heads uphill through the open grassland to the trail gate at Borges Ranch Trail.
Go straight to stay on Briones Mt Diablo Trail.
At the next trail junction, turn left onto Borges Ranch Trail. It name changes to Twin Ponds Trail as it drops downhill towards Rock Spring Creek to Twin Ponds.
Go straight on the unmarked Twin Ponds Trail through the cattle gate, it continues across the open grassland to the Foothills trail junction.
Continue straight onto Foothills Trail to the next junction at Stone Gate Trail.
Stay on Foothills Trail, it cuts across the grassland before coming to an end at the Stone Gate T junction.
Cross Stone Gate Trail and go straight onto Hanging Valley Trail, it winds southward around the flat valley followed by a moderate climb and a brief downhill section.
Stay on Hanging Valley Trail, the road tilts upwards with a steep climb up to the top of the ridge.
The trail continues southwards as it drops downhill.
Enjoy the fabulous naturally sculptured rock formations!
At the next junction, turn left onto Alamo Trail junction. The broad fire road turns eastward across the open grassland to the T junction at Briones Mt Diablo Trail.
Turn left onto Briones Mt Diablo Trail, it turns northerly with grand views of Mt Diablo and the lower ridges!
The trail gently winds downhill past a cattle pond to the Stone Gate junction.
Turn right to stay on Briones Mt Diablo Trail to Buckeye Ravine Trail.
The single track Buckeye Ravine Trail drops down through the gorgeous shaded buckeye/oak woodlands.
The trail exits the ravine with impressive views of the Castle Rock vertical sandstone formations!
At the trail split, go left, the trail comes to a T at the Stage Road Trail junction.
Go left and continue north on Stage Road. Vegetation varies from grassland and oak savannah on the hills to riparian and oak woodland in the valley. Pine Creek flows through Pine Canyon and is within the eastern portion of the Walnut Creek watershed, which drains 150 square miles of central Contra Costa County into San Francisco Bay.*1
Stage Road Trail continues through the woodland with views of the wonderous sandstone formations! Adjacent to Diablo Foothills is Castle Rock Recreation Area located in a scenic canyon along Pine Creek. The area is dominated by oak woodlands and prominent sandstone formations. Castle Rock has historically specialized in preparing picnic events for large groups of 300 or more people.*1
The sandstone trail drops downhill along the old spillway back towards Castle Rock Trail.
Turn right to stay on Stage Road Trail, it leads back to the Castle Rock Trail junction, go right to stay on Stage Rd.
At the green trail gate, stay to the right and follow the road into Castle Rock Park.
Walk through the recreational areas at Castle Rock Park for the return to the parking lot.
This is a fabulous hike around the scenic Diablo Foothills and the lower valley grasslands to Shell Ridge and Twin Ponds! You’ll enjoy the beautiful jaunt through Buckeye Ravine and the prominent sandstone formations!
6.1 Miles with 1158′ of elevation gain
Max elevation: 861′
Time: 3.5 hrs with one stop
Parking: No fee-Diablo Foothills Reg Park Trailhead parking-informal parking near the park entrance at the end of Castle Rock Rd in Walnut Creek
Water & restrooms at Castle Rock Park ~1/4 mile from the parking area
Weather: Sunny and warm. Temps ranged from the low 60’s to the mid 80’s with Se > ENE winds.
Directions: Diablo Foothills Reg Park Trailhead > L-Castle Rock Tr > L-stay on Castle Rock Lower Tr > S-Stage Rd > R-Fairy Lantern Tr > R-Shell Ridge > R-Shell Ridge Loop Tr > R-scramble downhill onto Briones Mt Diablo Tr > R-Briones Mt Diablo Tr > S-stay on Briones Mt Diablo Tr > L-Borges Ranch Tr > S-becomes Twin Ponds Tr > S-stay on Twin Pond Tr > S-Hanging Valley Tr > S-stay on Hanging Valley Tr > L-Alamo Tr > L-Briones Mt Diablo Tr > R-stay on Briones Mt DiabloTr > R-Buckeye Ravine Tr > L-Stage Rd Tr > R-stay on Stage Rd Tr > R-at trail split gate into Castle Rock Park > to parking lot