In 65 days · Fri, Jan 1, 2027
Don't let race day sneak up
One email during race week. That's it.
Friday, January 1st, 2027
17600 Lake Chabot Road, Castro Valley CA
5K · 10K · Half
44–56°F · some rain risk
See last 10 years
On this date: rain 1 of the last 10 years
2026
49–59°F
rain
2025
38–54°F
dry
2024
46–58°F
dry
2023
44–59°F
dry
2022
35–50°F
dry
2021
39–56°F
dry
2020
45–59°F
dry
2019
38–52°F
dry
2018
44–61°F
dry
2017
44–50°F
dry
Best months to race in California →
About this race
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.
Course map
Train with a club
Run clubs near Castro Valley to train with before race day.
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