By Devin Fehely

SAN JOSE (CBS SF) — The ribbon-cutting ceremony high atop Mount Umunhum was a moment more than three decades in the making.

“This has been a long, difficult project. It’s the biggest thing we ever tackled,” said General Manager Steve Abbors. “We’re so glad to be able to do this for the public.”

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One of the highest peaks in the Bay Area, the Midpeninsula Regional Open Space District bought the former hilltop Air Force base in 1986 but it’s languished off-limits and unused for lack of funds.

In recent years, a combination of federal funding and money from a local bond measure enabled the Open Space District to embark on a $25 million cleanup and restoration of the site.

The restoration pays homage to the site’s military history.

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The Open Space District removed several dozen buildings from the former military base but left intact “The Cube” — the concrete tower that once held a massive, rotating radar dish used to scan for Russian bombers.

The Open Space District also partnered with the Native American tribes who once called Mt. Umunhum home.

“We requested that there be a spiritual circle there. A place for ceremony – a place for dance,” said Aman Mutsah Tribal Chairman Valentin Lopez.

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The Sierra Azul Open Space Preserve which includes Mt. Umunhum officially opened to the public Monday, September 18. There are roughly 85 parking spots available on a first-come, first-serve basis.