The Anthony Chabot Regional Park owned by the East Bay Regional Parks District (EBRPD) was created in 1952 as Grass Valley Regional Park. A portion of the park was once part of the Rancho San Antonio owned by a Luis Maria Peralta, and a larger portion was once part of the 27,000 acre Rancho San Lorenzo owned by Don Guillermo Castro (namesake of the town of Castro Valley). These ranchos were predictably used for cattle ranching, but Castro had to sell his portion after accumulating massive gambling debts. The San Antonio portion land grant was not honored when the United States took possession of the area, and soon became owned by American settlers who predictably raised cattle. The Peoples Water Company of Oakland acquired the area for a watershed around the turn of the 20th Century. Lake Chabot Reservoir was constructed in 1875 as a reserve water supply for the City of Oakland, and was not opened for recreational use until 1966. The Peoples Water Company planted extensive groves of eucalyptus trees in a short-sighted attempt to foster a timber industry after the native California redwoods were chopped down.
This hike starts in the parking lot of the Willow Park Public Golf Course which is part of Chabot Park. There is an official trailhead called the Proctor Staging Area to the south on Redwood Road. The trail from Proctor to the golf course trail head features scenic views of a driving range and a huge net. We've always chosen the golf course trail head.... The trail begins at the southeast corner of the parking lot (north of the 19th Hole), and it's another maintained fire road. These fire roads are used to provide access to the semi-urban portions of the Bay Area so firefighters can bring heavy equipment to bear on wildfires. The hike begins by switchbacking back to the west above the parking lot, and the gain is relentless. You will eventually gain about 500 feet before the mellow portion of the trail.
The Brandon Trail is also part of the Skyline National Recreation Trail and also the Bay Area Ridge Trail. The former is fairly well-established from El Sobrante on the southern end to Wildcat Canyon Regional Park on the northern, and the latter is a trail that is planned to go around the entire Bay Area. There is a bench under some tall oaks about 1/2 mile in, and another bench after another mile. The hike here basically follows a ridge uphill with some decent views of Rocky Ridge and Sunol Ridge to the east through a fairly dense oak woodland.
After the 2nd bench there is a 3-way split: go left to take the Towhee Trail, right to stay on the official Brandon Trail for a .10 mile jaunt to a parking lot, or go straight to get to the highest point on this hike. You'll reach a low prominence covered with short chaparral with amazing views. San Francisco is easily visible on a clear day, and the area supposedly is a good place to see wildflowers in the spring. There is a faint trail from the top of the mountain down to the parking lot (accessed off of Marciel Road) or you can go back the way you came, and go left-backwards at the bench.
You will probably notice in the parking lot that this area is popular with mountain bikers. It most certainly is. The Brandon Trail is part of the Lake Chabot Bicycle Loop, and you will indeed see some cyclists no matter when you do this hike. The Brandon Trail continues from the northwest side of the parking area, and you quickly see the vegetation that is typical of this area. The trail is a fire road that goes through an open area with extensive stands of eucalyptus upslope to the east and in the canyons that flow down to the west. These trees were planted with the intention of not only stabilizing the soil after extensive logging of the native redwoods and oaks, but also for a prospective timber industry. The timber industry never took off, and now many worry that the dense stands of eucalyptus could turn into fiery infernos. The eucalyptus has basically replaced redwood and oak woodland in the west-facing areas in the East Bay, and form a monoculture wherever they are feral and prevalent.
The hike in this area is basically flat, but soon enough there are some ups and downs. You'll pass the Tow Rocks and Mirador trails before passing both legs of the Loggers Loop Trail, and all of these trails head steeply downhill to the west towards Grass Valley Creek. It's only 2 more miles along this fairly mellow and wide trail to its junction with the Deer Canyon Trail. Deer Canyon branches off to the right (east), and it's steep. Only 1/4 mile to the top, but it's straight up. Make a left onto the Redtail Trail which soon crosses Marciel Road, and continue north on it 1/3 mile to the Marciel Gate parking area.
That route takes you from the lower trail head at Willow Park Public Golf Course to the Marciel Gate. Instead of taking the Deer Canyon Trail you could continue along the Brandon Trail as it meanders along the contours down to Grass Valley Creek before crossing it and finally ending at the Clyde Woolridge Staging Area.
WARNING! Hiking and outdoor related sports can be dangerous. Be responsible and prepare for the trip. Study the area you are entering and plan accordingly. Dress for the current and unexpected weather changes. Take plenty of water. Never go alone. Make an itinerary with your plan(s), route(s), destination(s) and expected return time. Give your itinerary to trusted family and/or friends.