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Alum Rock Park – City of San Jose

Dedicated in 1872, Alum Rock Regional Park is California's oldest municipal park. Located in the foothills of the Diablo Mountain Range, the park is nestled within the steep confines of the Alum Rock Canyon along Penitencia Creek, which bisects the Park and flows year-round. Once home to the Ohlone Indians, Alum Rock Park features rugged ridges with spectacular views of the Santa Clara Valley, geologic formations including mineral springs and evidence of seismic events, and a wide variety of native flora and fauna (map).

The park’s 740 acres of natural, rugged, beauty provide visitors with many leisure outdoor activities including over 13 miles of unpaved hiking trails varying from fairly level along Penitencia Creek to sharp switchbacks climbing to the ridges to the South Rim and North Rim Trails. The northern trails are open to mountain biking and provide a gateway to the Santa Clara County Open Space Authority’s Sierra Vista Open Space Preserve. The narrow floor of the canyon includes a visitor center, picnic areas, a playground, and sand volleyball pits.

The canyon at Alum Rock has abundant mineral springs, which were touted as beneficial to people's health. In the late 1800s and through the 1930s, the park was famed throughout the country as a health resort. Through those years and as late as the 1970s, the park featured a natatorium (a huge, heated indoor swimming pool), dozens of private heated mineral baths that visitors could rent, a restaurant, and various other buildings. Many of the springs were enclosed in stonework grottos, and stone bridges were built across the creek. An electric railroad brought people from San Jose into the park. In the 1970s, the park removed most of the buildings and began emphasizing the park's natural attractions rather than its manmade ones. However much of the attractive stonework remains, as do old support structures for the railroad.

Special features of the park include 13 miles of hiking trails, the Penitencia Creek which transects the entire park, the Mineral Springs area that contains active mineral springs and grottos, the Gazebo and the Log Cabin which was constructed in 1913.

Website: Alum Rock Park Overview, Alum Rock Park Facility Details

Location: Alum Rock Regional Park, San Jose, California - South Rim Trail

Directions: Access is currently available only from Penitencia Creek Road. Use caution if following Internet-based maps to the park! Some lead you to a closed gate. The following address may be used to reach the park entrance with Bing, Apple or Google Maps.

Address: 15295 Penitencia Creek Road San Jose, CA 95132 - (408) 794-7275.

From San Francisco / the Peninsula:

  1. Take US-101 or I-280 south to I-680.
  2. Take I-680 north toward Sacramento (I-280 turns into I-680 in south San Jose).
  3. Take the McKee Road exit, and merge right onto McKee Road heading east towards the hills.
  4. Continue about 0.8 mile along McKee Road.
  5. Turn left on White Road, and continue about 1.2 miles.
  6. Turn right onto Penitencia Creek Road and follow it for about 1.2 miles to the Park Entrance.
  7. After entering the park, follow Penitencia Creek Road to the end of the park, about 2 miles. Speed limit is 20 MPH.
  8. Park and follow the signs to the Sycamore Grove Picnic area / Sycamore Switchbacks Trail trailhead.
  9. Be sure to display your parking pass on front windshield.

From Oakland / I-880 corridor:

  1. Take I-880 south toward San Jose.
  2. Take the Warren Ave/Mission Blvd exit toward I-680. Keep left, follow signs for Mission Blvd/I-680 and continue onto Mission Blvd.
  3. Take the I-680 S ramp toward Milpitas. Merge onto I-680.
  4. Take the Berryessa Rd exit.
  5. Keep left at the fork, follow signs for Berryessa R. East, merge onto Berryessa Rd and continue for about 0.6 mile.
  6. Turn Right onto N Capitol Ave and continue for about 0.3 mile.
  7. Turn left onto Penitencia Creek Rd and follow it for about 2 miles to the Park Entrance.
  8. After entering the park, follow Penitencia Creek Road to the end of the park, about 2 miles. Speed limit is 20 MPH.
  9. Park and follow the signs to the Sycamore Grove Picnic area / Sycamore Switchbacks Trail trailhead.
  10. Be sure to display your parking pass on front windshield.

From the East Bay / I-680 Corridor:

  1. Take the I-680 S toward San Jose.
  2. Take the Berryessa Rd exit.
  3. Keep left at the fork, follow signs for Berryessa R. East, merge onto Berryessa Rd and continue for about 0.6 mile.
  4. Turn Right onto N Capitol Ave and continue for about 0.3 mile.
  5. Turn left onto Penitencia Creek Rd and follow it for about 2 miles to the Park Entrance.
  6. After entering the park, follow Penitencia Creek Road to the end of the park, about 2 miles. Speed limit is 20 MPH.
  7. Park and follow the signs to the Sycamore Grove Picnic area / Sycamore Switchbacks Trail trailhead.
  8. Be sure to display your parking pass on front windshield.

Agency: San Jose Department of Parks, Recreation & Neighborhood Services

Supervisor: Bill Farrell

Project Lead: Larry Stites

Additional Information: Participants should bring water, sunscreen, sturdy shoes, lunch and normal precautions against poison oak exposure (work gloves, long sleeved shirts and long pants).

It can be quite cool in the canyon so dress in layers.

The Trail Center provides tools, training, gloves, and refreshments after the workday.

SIGNUP REQUIRED

The park normally imposes a $6.00 parking fee. Signup for the event to receive a free day-pass and notification of any schedule changes.

Inclement weather conditions may postpone this event.

  • Volunteers 14 and under require prior approval by the project manager and must be accompanied by a parent or guardian.
  • Individual volunteers age 15 to 17 require a waiver signed by a parent or guardian.
  • Groups of volunteers age 15 to 17 require a waiver signed by a parent or guardian for each individual and must be accompanied by one or more supervising adults for every 5 minors.
  • Contact the trail center (volunteer@trialcenter.org) to obtain approval and waivers prior to arrival.

Meet at 8:30 a.m. for safety talk and crew assignments. We will start work at 9:00 a.m. and end at 3:00 p.m.