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 19th 2025! 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
Prices are inclusive of mandatory charges, items, and fees
5K Closed
Online registration closed-
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$69.50Oct 12 – May 12
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$74.84May 12 – Jun 16
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$80.18Jun 16 – Jul 27
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10K Closed
Online registration closed-
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$79.11Oct 12 – May 12
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$84.45May 12 – Jun 16
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$89.79Jun 16 – Jul 27
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Half Marathon Closed
Online registration closed-
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$100.46Oct 12 – May 12
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$105.80May 12 – Jun 16
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$111.14Jun 16 – Jul 27
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Remote Runner Closed
Online registration closed-
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$60.96Oct 12 – Jun 29
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$66.30Jun 30 – Jul 27
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Event schedule
- Sat, July 19, 2025 7:30 AM - Hiker start (for those walking the half marathon, planning to take longer than 3.5-4 hours)
- Sat, July 19, 2025 8:30 AM - Half Marathon
- Sat, July 19, 2025 8:55 AM - 10K
- Sat, July 19, 2025 9:10 AM - 5K
Contact information
- Event contact
- Race Director
- Website
- Visit website
