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!
Registration fees
Where pricing applies, shown amounts include mandatory charges, items, and fees.
5K
Registration closes in 16 days 4 hours-
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Register for 5K$80.18Now registering Jun 22 – Jul 18
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10K
Registration closes in 16 days 4 hours-
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Register for 10K$89.79Now registering Jun 22 – Jul 18
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Half Marathon
Registration closes in 16 days 4 hours-
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Register for Half Marathon$109.00Now registering Jun 22 – Jul 18
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Remote Runner
Registration closes in 16 days 4 hours-
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$60.96Oct 11 – Jun 27
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Register for Remote Runner$66.30Now registering Jun 28 – Jul 18
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Event schedule
- Sat, July 18, 2026 7:30 AM - Hiker start (for those walking the half marathon, planning to take longer than 3.5-4 hours)
- Sat, July 18, 2026 8:30 AM - Half Marathon
- Sat, July 18, 2026 8:55 AM - 10K
- Sat, July 18, 2026 9:10 AM - 5K
Contact information
- Event contact
- Race Director
- Website
- Visit website
