In 54 days · Sat, Oct 17, 2026
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Saturday, October 17th, 2026
Castle Rock Rd, Walnut Creek CA
Half · 5K · 10K
55–76°F · low rain risk
See last 10 years
On this date: rain 1 of the last 10 years
2025
49–72°F
dry
2024
54–74°F
dry
2023
60–83°F
dry
2022
52–74°F
dry
2021
49–71°F
rain
2020
65–92°F
dry
2019
55–71°F
dry
2018
50–79°F
dry
2017
59–85°F
dry
2016
53–67°F
dry
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About this race
Race Overview
Join us for the Diablo Summit Stomp 2026 on October 17, 2026, at Castle Rock Rd, Walnut Creek, CA. For more information, visit Race Roster.
Course Details
- Trail-Based: All courses are on trails.
- Hill Challenges: While there are some hills, the event is designed to be friendly to all runners.
- Inclusive: First-time trail runners and experienced runners alike will find it enjoyable.
- Walkers/Hikers: Walkers and hikers are welcome in all distances.
Awards Information
- Age Group Awards: Awards will be given to the top 3 finishers in each age group.
- Categories: Awards will be distributed in 5-year categories, with smaller categories for younger ages.
- Recognition: Celebrate your achievements with fellow runners.
- Participation: All finishers are recognized and celebrated.
Course map
Train with a club
Run clubs near Walnut Creek to train with before race day.
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