Russian Ridge Open Space Preserve, Regional park in San Mateo County, California.

Russian Ridge Open Space Preserve is a 3,137-acre regional park in the Santa Cruz Mountains, managed by the Midpeninsula Regional Open Space District. It contains dense forest and open meadows, and its 10.4 miles of trails include the Ridge Trail, part of the Bay Area Ridge Trail. Borel Hill, at 2,572 feet, is the highest point.

Russian Ridge takes its name from a Russian immigrant, Mr. Paskey, who leased a dairy farm here from James "Sunny Jim" Rolph Jr. between the 1920s and 1950. Rolph was then mayor of San Francisco and later California's 27th governor. The Midpeninsula Regional Open Space District began acquiring the land in 1978 from owners who had planned to subdivide it.

The name comes from Mr. Paskey, a Russian immigrant who leased a dairy farm on this land from the 1920s to 1950 from James "Sunny Jim" Rolph Jr., then mayor of San Francisco and later California's 27th governor. The dairy operation is gone, but the name he left on the ridge remains.

The preserve is accessible through two main entry points: roadside parking along Skyline Boulevard and a dedicated lot at the Audrey C. Rust Commemorative Site. Visitors should be prepared for variable weather conditions and changing trail conditions due to elevation changes across the landscape.

From Borel Hill, the highest point in the area at about 2,572 feet (784 m), visitors can see both San Francisco Bay to the east and the Pacific Ocean to the west on clear days. This rare vantage point bridges two distinct coastal regions from a single location.