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Date:
Thu, Dec 31, 2026 at 7:30 AM
Location:
Lake Chabot Road
Alameda County, California
94546
United States
OpenStreetMap Google Maps
Links:
brazenracing.com Register at raceroster.com
Tags:
10k 21k 5k Run Trail Virtual

Whether you're looking to squeeze in your first trail run or you're looking to log that 1,000th mile before the clock strikes midnight on 12/31/2026, this is your chance.

Note: This year we will have back-to-back events at Lake Chabot, Castro Valley with a 5K, 10K and half marathon!

New Year's Eve, Thursday, 12/31/2026

New Year's Day, Friday, 1/1/2027*

Make it a double and join us both days and earn the Brazen New Year Mega-Medal!

*Note: Each race is a unique event on its own and requires separate registration.

More races nearby

  • Lake Sonoma 50 [lakesonoma50.com]

    Sat, Apr 11, 2026

    2.8 km
    Hawk Ridge Trail, Sonoma County, California, United States
    OpenStreetMap Google Maps

    50 Miles Half Marathon Marathon Run

  • SPASM Lake Chabot Trail Run [runsignup.com]

    Sat, Apr 11, 2026 at 8:20 AM

    Description

    The course starts at the Marina and travels around the popular Lake Chabot reservoir and surrounding hills. Great course for first-time trail runners!

    (Distances are accurately measured using a Rolatape® surveyor's measuring wheel.)

    2.7 km
    Alameda County, California, 94546, United States
    OpenStreetMap Google Maps

    2 Miles 3.1 Miles 5 Miles 13.1 Miles 17.9 Miles 26.2 Miles 31 Miles Run Trail

  • 2026 Lake Chabot Trail Challenge (Half Marathon & 5K) [runsignup.com]

    Sun, Jun 07, 2026 at 8:00 AM

    Description

    “Beginning July 1, 2024, the “Honest Pricing Law” or “Hidden Fees Statute,” SB 478, makes it illegal for businesses to advertise or list a price for a good or service that does not include all...

    “Beginning July 1, 2024, the “Honest Pricing Law” or “Hidden Fees Statute,” SB 478, makes it illegal for businesses to advertise or list a price for a good or service that does not include all required fees or charges other than certain government taxes and shipping costs.”

    RACE INFO: We are so excited to celebrate the 42nd annual Lake Chabot Trail Challenge Half Marathon and 5K. This race is well regarded amongst serious trail runners in the outlying areas. The race begins at 8am for the Half Marathon and 8:30am for the 5K. Please arrive early so that you may find parking, pick up your bibs, use restrooms facilities, and be properly prepared to race before the start. Race takes place rain or shine and there are no refunds.

    RACE COURSE: The half marathon course is a scenic, hilly loop, mainly on dirt fire roads. The ridge-line views look down upon scenic Lake Chabot, surrounding grassy slopes, and eucalyptus groves. Mt. Diablo and San Francisco Bay are visible along the route. There are water stations with first aid and radio support; we recommend bringing your own hydration as well. The half marathon has a time limit of 3.5 hours. The 5k (3.1 miles) course is an out and back that has gentle rolling hills and consists mostly of paved surfaces. This route includes one water station with first aid and radio support.

    RACE FEE: Pre-registered runners will be guaranteed a t-shirt if registered by Sunday, May 10th, 2026. The price for the 5K is $40 and Half Marathon $65. You must register by Saturday, June 6th. We will accept race day registration; however, the price for the 5K is $45 and Half Marathon $70. If you register on race day, we can only accept cash, check or Venmo.

    There is a nominal fee (~$5) for Chabot parking lot. Free parking on Lake Chabot Rd and nearby streets.

    RACE PACKET & BIB PICK-UP: We will have race packet and bib pick-up on Sunday, June 7th starting at 7am at the Willow picnic site which is also the finish line area. We will not be mailing out any race packets or bibs. Both races are chip-timed.

    T-SHIRT: Entry fee includes short sleeve, high quality t-shirts for registrations by May 10th so sign-up early. There are no guarantee of t-shirts for runners registered after that date and on race day. We ask for those who did not get a shirt to check in after the race. Please ensure that you select the appropriate t-shirt size. We will not be doing any size exchanges from your original request.

    AWARDS: Finisher's medals to those who complete their race. Age division medals given to the top 3 in each of 12 age divisions in the half marathon and 9 age divisions in the 5K.

    Photos: Race photos are being provided by Darrell Lavin of Darrell Lavin Photography. You will receive an email post-race for instructions on how to access and purchase official race photos.

    QUESTIONS: If you have any questions, please contact Rachel Lunt at teamlunt07@gmail.com.

    DIRECTIONS: The entrance closest to the event's parking lot is: 17404 Lake Chabot Road, Castro Valley, CA 94546. On Google Maps, this will appear as "Entry of Lake Chabot Parking Space." The registration area and start lines are just a few minutes walk from the lot ( just follow the signs).

    2.7 km
    17404 Lake Chabot Road, Alameda County, California, 94546, United States
    OpenStreetMap Google Maps

    3.1 Miles 5k 13.1 Miles Half Marathon Run Trail Walk

  • Bad Bass 2026 [brazenracing.com] [Register at raceroster.com]

    Sat, Jul 18, 2026 at 7:30 AM

    Description

    Rising up from the depths of Lake Chabot, the Bad Bass (a strangely kilt-wearing, bagpipe-playing Scottish bass with teeth) shows itself once again on July 18th 2026! Why is he Scottish? What is he...

    Rising up from the depths of Lake Chabot, the Bad Bass (a strangely kilt-wearing, bagpipe-playing Scottish bass with teeth) shows itself once again on July 18th 2026! Why is he Scottish? What is he doing in Castro Valley? How can he play bagpipes with his fin? We have no idea how to answer those questions. Why is he so bad-to-the-fishbone? Maybe he just knows how awesome the trails of Lake Chabot really are!

    Whatever the Bad Bass is doing here, we hope you'll join us at the beautiful Lake Chabot Marina in Castro Valley for the scenic Bad Bass 5K, 10K or Half Marathon!

    114 m
    West Shore Trail, Oakland, California, 94578, United States
    OpenStreetMap Google Maps

    5k 10k 21k Run Trail

  • Summer Breeze Half Marathon 10K & 5K [finishers.com]

    Sat, Aug 01, 2026

    4.8 km
    San Leandro, California, United States
    OpenStreetMap Google Maps

    5k 10k Half Marathon Run Trail

More races nearby →

Local running event organizers & groups

  • Special Olympics Northern California Event Organizer 25.4 km
    [p2p.onecause.com]

    Run

    3480 Buskirk Ave., Suite 340, Pleasant Hill, California, 94523-4382, United States
    OpenStreetMap Google Maps
    Phone: 9259448801 x224
  • Founders Running Club Group 28.7 km
    [foundersrc.com] [runningcrews.com] - Facebook - Instagram

    Founders Running Club (FRC) is an extraordinary running crew born in the heart of San Francisco's innovative startup culture in June 2022. Founded by tech entrepreneur Tim, the crew's mission is to unite founders, tech professionals, investors, creators, and their friends through a shared passion for running. With a weekly run in San Francisco and a rapidly growing global presence in cities like Amsterdam, Boston, and Copenhagen, FRC has become a worldwide movement built on the principles of community, personal growth, and the relentless spirit of entrepreneurship.

    Community Run

    San Francisco, California, United States
    OpenStreetMap Google Maps
  • Golden Gate Running Club Group 28.7 km
    [goldengaterunningclub.org] [runningcrews.com] - Facebook - Instagram

    Golden Gate Running Club (GGRC) is a non-profit, member-driven running club that perfectly embodies the "runs hard and plays hard" spirit of San Francisco. United by an enthusiasm for running among friends in one of California's most beautiful cities, they cater to a diverse range of needs, from serious marathon training to casual, conversational runs. Their structured schedule includes Wednesday night track practices at Kezar Stadium and scenic Sunday runs from Crissy Field. With a focus on community, member dues are used to subsidize races and a vibrant calendar of social events, including monthly happy hours and an annual banquet.

    Community Run Social

    San Francisco, California, United States
    OpenStreetMap Google Maps
  • Unseen Run Club Group 29 km
    [runningcrews.com] [runningcrews.com] - Instagram

    Founded in January 2023 by Justin, who sought to foster genuine connection and diversity within San Francisco’s running community, Unseen Run Club has grown into a close-knit group of around 40 runners. Embracing inclusivity and resilience, the crew welcomes runners of all backgrounds and abilities, encouraging members to challenge their limits without judgment. Weekly Tuesday evening runs through the city’s iconic hills and waterfront create a space for meaningful conversation and friendship, while monthly events at Groundfloor San Francisco blend running with the city’s vibrant artistic scene. Beyond casual runs, members participate in local races and ultramarathons, reflecting a shared commitment to endurance and growth. As a distinct voice in San Francisco’s rich running network, Unseen Run Club celebrates the city’s diverse culture and landscape, inviting all to experience running as a way to connect, explore, and belong.

    Community Run

    San Francisco, California, United States
    OpenStreetMap Google Maps
  • DSE Runners Event Organizer 34.6 km
    [dserunners.com]

    Run

    San Francisco, California, 94121, United States
    OpenStreetMap Google Maps
    Phone: 4159780837
See all organizations →
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