2026 Lake Chabot Trail Challenge (Half Marathon & 5K)

Lace up for the 42nd annual Lake Chabot Trail Challenge, a beloved event that invites runners to experience the stunning natural beauty of Castro Valley, California, on Sunday, June 7, 2026. This race is well regarded among serious trail enthusiasts in the East Bay, offering both a challenging Half Marathon and a scenic 5K. Both distances are chip-timed and start and finish near the Lake Chabot Marina at the Willow picnic site, promising a vibrant race day atmosphere.

The Half Marathon course is a memorable, hilly loop predominantly on dirt fire roads, renowned for its rugged terrain and significant elevation changes. Runners will be treated to breathtaking ridge-line views overlooking Lake Chabot, expansive grassy slopes, and fragrant eucalyptus groves, with distant panoramas of Mt. Diablo and the San Francisco Bay. Five aid stations equipped with water, first aid, and radio support are strategically placed along the half marathon route, though carrying personal hydration is advisable for this demanding course. For those seeking a shorter yet equally rewarding experience, the 5K features gentle rolling hills on mostly paved surfaces and includes one water station with first aid and radio support. Typical race day conditions in early June offer pleasant weather, with highs around 73°F and lows around 55°F, and only a 1% chance of precipitation, creating an ideal environment for a challenging and picturesque run.