The Rock The Loch Half Marathon

Castro Valley, United States • 27-30 Jun 2025

The Rock the Loch Half Marathon is a scenic trail running event held at Lake Chabot Regional Park in Castro Valley, California. Scheduled for late June 2025, it offers live and virtual participation options across three distances: 5K, 10K, and half marathon. The 5K is fully paved, ideal for beginners or fast runners, while the 10K combines paved and trail sections with a challenging climb. The half marathon features mostly trail terrain with nearly 1,700 feet of elevation change, suited for experienced trail runners. Participants enjoy aid stations with hydration and snacks, race swag including a custom shirt, handcrafted woodallion, and a beer sampler stein, plus post-race refreshments and a brewfest with music by DJ Cryptid. Visit the organization's website for the most recent information.

Race information

13 mi
Half Marathon (live)
10 km
10k (live)
5 km
5k (live)
10k (virtual)
5k (virtual)
Half Marathon (virtual)
Visit the organization's website for the most recent information.
Trail runs nearby

The Mt. Umunhum Marathon, Race to the Top and Down, is a challenging trail running event held in Almaden Quicksilver County Park, San Jose, California. This marathon features a rugged course that begins at the Hacienda Entrance and ascends to the summit of Mt.Umunhum, one of the prominent peaks in t..

Rocky Ridge is a trail race set in the Las Trampas Wilderness near San Ramon, California. The event offers a half marathon, a 10K, and a 5K through rugged hills and scenic vistas. The course is demanding and not beginner-friendly, rewarding perseverance with trails and views few runners will see, fo..

Pacifica Summit Run, staged at San Pedro Valley State Park in Pacifica, California, features 10K and half-marathon trail races hosted by Urban Coyote Racing. Runners enjoy postcard views of the Pacific Ocean coastline and plenty of switchbacks as they ascend the summit on the upper San Francisco Pen..

Dick Collins Firetrails is the 42nd annual trail event presented by Scena Performance at Lake Chabot Regional Park (17936 Lake Chabot Rd). The event comprises multiple trail races on East Bay regional trails, including sections on Dinosaur Ridge, the Garin-Chabot Trail, Skyline Gate, Reinhardt Redw..

UTMB Index

Spartan Trail San Jose Challenge takes place at Sanborn County Park in the eastern Santa Cruz Mountains near Saratoga, California, with the race site at West Valley College Parking Lot 5. The event offers three trail distances: 50K, 21K, and 10K. Runners tackle well‑groomed yet steep and difficult t..

The Trailblazer Race in Mountain View, CA, is an annual family-friendly event featuring 10K and 5K runs, plus a 3-mile walk along the scenic Stevens Creek Trail and Shoreline Park. The courses are fast, flat, and stroller-friendly, offering beautiful views of wildlife, salt ponds, and surrounding mo..