Ridge-to-Ridge Challenge

Rising majestically above the Diablo Valley, Mount Diablo stands as the iconic symbol of central Contra Costa County. Nestled at its base is Walnut Creek, a vibrant community defined by its close relationship with the surrounding hills of the Diablo Range.
More than 50 years ago, a small group of visionary residents worked tirelessly to preserve the rolling ridges and grassland valleys of Shell Ridge Open Space, including Fossil Hill and Joaquin Ridge. Thanks to their dedication, these lands remain protected and open for everyone to enjoy.

The Ridge-to-Ridge Challenge is an annual fundraiser supporting Sustainable Contra Costa and its youth program, Sustainable Leaders in Action (SLIA). Each year, high school and college students collaborate to raise awareness about climate issues and inspire meaningful, sustainability efforts throughout Contra Costa County.

Choose Your Ridge-to-Ridge Experience
Participants will gather at the south end of Marshall Drive at 8:45am for opening remarks.

• Fossil Hill Scavenger Hunt (~1.4 miles): A fun, interactive walking loop around Fossil Hill. Individuals or teams follow puzzle-style clues to locate scavenger points along the course. Participants photograph each location and race back to the finish once all points are found.
• Start Time: 9:15 AM
• Indian Valley Nature Walk (~1.4 miles): A relaxed, educational walk featuring short talks from local experts on topics such as: Geology of Shell Ridge, Indian Creek restoration, History of Quarry Hill and Fossil Hill, Native plants and habitat restoration and Wildlife of the open space.
• Start Time: 9:15 AM
• Ridge-to-Ridge Challenge Run (5K / 3.1 miles): A challenging and scenic trail run through the hills and valleys of the open space.
• Start Time: 9:00 AM

Register here, and get maps and all the details.