On this page
For more than a century, the hills south of San Jose were one of the most valuable pieces of ground in California. The New Almaden mines produced mercury, called quicksilver, which miners needed to pull gold out of crushed ore during the Gold Rush. Today those hills are Almaden Quicksilver County Park: 4,163 acres covering most of Capitancillos Ridge, with sealed mine portals, old furnace foundations and more than 37 miles of trail.
It is one of the best spring hikes within an hour of Palo Alto. Santa Clara County Parks counts it among the region's best early-spring wildflower displays. It is also one of the few county parks that charges no fee. Leashed dogs are welcome on every trail. This guide covers the entrances, trails and rules, the mining story and the safety notes that come with any South Bay foothill park.
Getting there and entrances
From Palo Alto, take Interstate 280 south to Highway 85, then continue toward south San Jose. Allow about 35 to 45 minutes outside rush hour. The county lists three main entrances, all reached from Highway 85:
| Entrance | County directions | Notes |
|---|---|---|
| Mockingbird Hill | Almaden Expressway south 4.5 miles to Almaden Road, then 0.5 miles to Mockingbird Hill Lane; turn right and drive 0.4 miles to the lot | Open to all users, including bikes; drinking water |
| Hacienda | From Almaden Expressway, 3 miles along Almaden Road through New Almaden to the unpaved staging area on the right | Open to all users, including bikes; drinking water; closest to the museum |
| Wood Road | Camden Avenue exit, south to Hicks Road, then 6 miles to Wood Road; turn left into the staging area | On the west side, near Guadalupe Reservoir |
The county also names a McAbee entrance at the north end. Check the county's park page for current entrance notices; the county site refuses automated checks, so read it in a browser.
The Hacienda entrance sits at the south end of New Almaden, a small historic village along Alamitos Creek. Parking there puts you a short walk from the mining museum. Mockingbird Hill is the busiest trailhead on weekends.
Hours and fees
- Hours: open year-round, 8 a.m. to sunset.
- Fees: none at any entrance.
- Picnics: tables are scattered along the trails rather than grouped in one area.
- Trail closures: the county may close trails after heavy rain when the ground is too soft. Clay soils here get slick fast.
The county's park office number is (408) 535-4070. For a broader look at fees across the county system, our Stevens Creek County Park guide lays out the standard $6 day-use charge that applies in most other county parks.
Trails
The county counts more than 37 miles of trail for hikers, about 30 miles open to horses and about 16.6 miles open to bikes. It does not publish distances for individual trails on its park page, so download the county trail map before you go. Cell service on the ridge can be patchy.
Most routes start low, under 600 feet at the east-side entrances. They climb steadily onto the ridge. Wikipedia puts the park's high point above 1,700 feet. From the top you look north over the whole Santa Clara Valley and south toward Mount Umunhum. Expect fire roads with long climbs and little shade on the south-facing slopes, plus shadier oak woodland on the north side.
Along the way are the remains of the mining era. Wikipedia describes structures scattered across the park, with the largest concentration at English Camp, settled by Cornish miners in the 1860s. It also names the ruins of the Senador Mine. The county reminds visitors not to climb on any structure.
To the west, the park meets Midpen's Sierra Azul Preserve; our Sierra Azul page notes that its Woods Trail connects east into Almaden Quicksilver. Strong hikers can link the two for a long day.
Horse riders will find water troughs at a few locations, the county says. Our horseback riding guide lists stables closer to Palo Alto.
The New Almaden mines
The National Park Service calls New Almaden California's first mining operation. Mexican settler Antonio Suñol found the ore deposits in the 1820s. Mexican Army officer Andrés Castillero identified them as quicksilver in 1845, before the Gold Rush. The mines took their name from the famous mercury mines of Almadén in Spain. Under the Quicksilver Mining Company, New Almaden became the most prominent quicksilver mine in the Western Hemisphere, according to the Park Service.
The county says mining went on for more than 135 years and that more than 1,800 miners and their families lived on the site. Wikipedia gives the operating years as 1847 to 1976 and says more than 83 million pounds of mercury were taken out. Santa Clara County bought the mining land in the mid-1970s and opened the park soon after. The New Almaden district is a National Historic Landmark.
Today all mines and adits are sealed. The San Cristobal mine can be viewed from behind a locked gate.
New Almaden Quicksilver Mining Museum
The county runs the New Almaden Quicksilver Mining Museum at 21350 Almaden Road, in the Casa Grande building in New Almaden village. The Park Service says the museum opened in 1997 and displays the collection of Constance Perham, covering mercury mining, blacksmithing and life in the mining camps. The county says hours vary and guided tours are available on request. Call (408) 918-7770 before you go.
Mercury and the reservoirs
The mining left a legacy in the water. The county warns that mercury in Guadalupe and Almaden reservoirs has reached levels that make fish from those reservoirs unsafe to eat. Sediment containing mercury from the old mine workings has reached local reservoirs and streams. Bacteria can turn it into methylmercury, which builds up in fish. Questions go to the county's Environmental Health Services at (408) 918-3400.
The county's warning is about eating fish. Even so, do not eat fish from the reservoirs, do not dig in or collect rocks from mine areas and wash hands after a picnic. Our fishing guide covers safer places to cast.
Dogs, bikes and horses
- Dogs: allowed on all trails on leash, the county says. Its general rules set a 6-foot maximum leash. Owners must pick up after their dogs. This makes the park one of the best dog hikes in the South Bay; see our dog-friendly hikes guide.
- Bikes: about 16.6 miles of trail are open to bikes. Use the Mockingbird Hill or Hacienda entrance. County rules require helmets for riders of every age on unpaved trails and ban fully electric bicycles in county parks. Our mountain biking guide covers more rides.
- Horses: about 30 miles of trail are open to riders, with troughs at a few spots.
- Mine structures: do not climb on them or try to enter sealed portals.
Seasons and safety
Early spring is the best time to come, when the grass is green and the county's wildflower displays peak. Summer is hot and dry, with little shade on the climbs. Start early and carry more water than you think you need. In fall the ridges are brown and dusty until the first rains. Our wildflowers guide has bloom timing for other parks.
Good to know
- Poison oak is a common hazard here; Wikipedia illustrates the park with it. Learn the three-leaf pattern and keep to the middle of the trail.
- Ticks are active from fall through spring. Check yourself and your dog afterward.
- Rattlesnakes come out on warm days. Watch where you put hands and feet.
- Mountain lions and bobcats live in these hills. Keep children close. If you meet a lion, stand tall, make noise and back away slowly.
- Trails may close after heavy rain. Call 911 in an emergency.
What pairs nearby
- Sierra Azul and Mount Umunhum: drive up Hicks Road to the summit radar tower.
- New Almaden village: walk the historic street along Alamitos Creek and visit the mining museum.
- San Jose: food and museums in the city below.
Frequently asked questions
Does Almaden Quicksilver County Park charge a fee?
No. Santa Clara County lists no fees at any of the park's entrances, unlike most county parks, which charge $6 for day use. Parking at the staging areas is free.
Are dogs allowed at Almaden Quicksilver?
Yes. The county says dogs are allowed on all trails in the park on a leash. The county's general rules call for a leash no longer than 6 feet. Owners must clean up after their dogs.
Can you go inside the old mines at Almaden Quicksilver?
No. The county says all mines and adits are sealed. The San Cristobal mine can be viewed from behind a locked gate. Visitors should not climb on any of the old structures.
Which Almaden Quicksilver entrance allows bikes?
The county says the Mockingbird Hill and Hacienda entrances are open to all users, including bicyclists. Both have drinking water. The park has about 16.6 miles of trail open to bikes. Check the county's trail map for which routes are open.
Is it safe to eat fish from Almaden or Guadalupe reservoirs?
No. The county warns that mercury in Guadalupe and Almaden reservoirs has reached levels that make fish from them unsafe to eat. Mercury-laden sediment from the old mines washed into local streams, where bacteria turn it into methylmercury that builds up in fish.