Midpen at 50More pieces in this series exploring the open space district’s history and work.
• Caring for the Land That Cares For Us How Midpen was born from a grassroots campaign.
• The Revival of a Clear Creek With old logging roads transformed, clean water and wildlife return to El Corte de Madera.
• Room to Roam Connecting protected spaces is key to wildlife conservation.
• Coexistence: Cattle Ranching Meets Sensitive Species When livestock and conservation needs align.
Dancers from the Amah Mutsun Tribal Band in traditional regalia circled a fire atop Mount Umunhum. The beat of a foot drum punctuated the song as it drifted with the wisps of smoke. It was 2017, and this was the tribe’s first ceremony on the summit in more than 200 years—the culmination of a long restoration effort in partnership with Midpen.
Mount Umunhum rises south of San Jose and lies within the ancestral territory of the Amah Mutsun Tribal Band, the Muwekma Ohlone Tribe of the San Francisco Bay Area, and other Indigenous peoples. For the Amah Mutsun, the 3,486-foot peak holds spiritual significance, playing a central role in the tribe’s origin story.
The Mutsun people were forcibly displaced by Spanish missionaries beginning in the late 18th century. Accessing the peak became only more difficult for the tribe, and for the general public, as time went on: in the late 1950s, construction of the Almaden Air Force Station closed off the summit.
Midpen acquired the site six years after the radar station shuttered in 1980, adding it to the Sierra Azul Open Space Preserve. But it wasn’t until 2009 that Midpen received federal funding for cleanup, which required removing 3,000 cubic yards of hazardous materials like asbestos and fuel containers.
The $25 million project also added viewing areas, picnic tables, and a series of ADA-accessible trails that spiral toward a ceremonial circle designed in consultation with the Amah Mutsun. The tribe now holds a cultural conservation easement on the summit—an agreement establishing permanent rights to partner with Midpen in stewarding the site.
“It’s important that we pray to the four directions, so we told Midpen we’d like the top to be returned for prayer,” says tribal chairman Valentin Lopez. “We’re very fortunate that our tribe found a way to carry on our traditional ceremonies as our ancestors did.”
The project also opened Mount Umunhum to the general public, who can now access the summit by road or a new multiuse trail. On a clear day, the views stretch from the Pacific to the Sierra Nevada.
“Today, you have little kids and grandmas driving up to the summit and taking in a view that they’ve never seen before,” says Midpen senior resource specialist Aaron Hébert. “We took something that was problematic—an abandoned Air Force station full of hazardous materials—and converted it into this beautiful open space.”
The summit does still feature a prominent remnant of its military past—one visible for miles. Nearby residents know the 85-foot-tall concrete structure as “the cube” or “the box”: the centerpiece of the old Air Force station, once topped by a radar antenna that scanned the skies for Soviet attackers.
While dozens of other structures were demolished as part of the cleanup, the cube was not. Citing its status as a local landmark, Santa Clara County officials designated the building a historical resource, and Midpen contractors restored the tower’s military-gray exterior to seal it from the elements.
Elsewhere, remnants of military construction physically became a part of the restoration effort. Rock and soil previously cast aside to clear space for station buildings was used to reshape the contours of the mountaintop. Then, Midpen began a multiyear effort to revegetate the land and make it more hospitable for wildlife.
Staff and volunteers installed elevated nesting boxes and other shelters for purple martins, a bird so rare in Santa Clara County that it was thought to have been extirpated altogether before a small breeding population was discovered on Mount Umunhum. At lower elevations, the endemic and rare Santa Cruz kangaroo rat has also been spotted.
The tough conditions on the summit favor hardy plants such as rock buckwheat, California fuchsia, and foothill penstemon. Amanda Mills, a resource specialist, led a team of staff and volunteers revegetating Mount Umunhum with natives like these. “All of the seed was collected from the Mount Umunhum area to maintain genetic integrity,” Mills says.
For the Amah Mutsun and their Midpen partners, the work of restoration is not over. One project under consideration nearby is a garden to support culturally significant plants, such as those used for food, medicine, and basket weaving. More ceremonies will take place, too.
“The ceremonies are offered for healing, for renewal, and for the environment. We also thank our ancestors for taking care of the earth as they did, for keeping the lands sacred.” Lopez says. “It’s important that we work hard to continue to restore our ways and to teach them to future generations.”
Midpeninsula Regional Open Space District is a public agency whose mission is to acquire and preserve a regional greenbelt of open space land in perpetuity, protect and restore the natural environment, and provide opportunities for ecologically sensitive public enjoyment and education.
On the San Mateo County coast, Midpen’s mission also includes acquiring and preserving in perpetuity open space land and agricultural land of regional significance, preserving rural character, and encouraging viable agricultural use of land resources. OpenSpace.org