3 events in San Mateo County, California

From big races to Saturday morning group runs—find half marathon events and connect with the local endurance sports community.

Woodside Ramble [ultrasignup.com]
Sat, Dec 20, 2025

5k 10k 35k 50k Half Marathon Ultra
San Mateo County, California, United States
OpenStreetMap Google Maps
Horseshoe Lake Half Marathon [stevenscreek.com] [Register at ultrasignup.com]
Sun, Mar 22, 2026 at 9:00 AM

Half Marathon
Skyline Ridge Open Space Preserve, San Mateo County, California, United States
OpenStreetMap Google Maps

Woodside/Purisima Creek Crossover [insidetrail.com] [Register at ultrasignup.com] - Facebook
Sat, Apr 18, 2026

10k 35k 50k Half Marathon Ultra
1100 Kings Mountain Rd, San Mateo County, California, 94062, United States
OpenStreetMap Google Maps

Local Clubs & Organizations

Highland Dolphins Aquatic Club Club

[teamunify.com] [usaswimming.org]
USA Swimming Club. 49 members.

Swim

Contact: ronberry100@gmail.com
1851 Lexington Ave, San Mateo County, California, 94402-4026, United States
OpenStreetMap Google Maps
Phone: +1 925-383-9556
Ladera Oaks Club

[teamunify.com] [usaswimming.org]
USA Swimming Club. Club Excellence: Bronze. 55 members.

Swim

Contact: kayla@laderaoaks.com
3249 Alpine Rd, San Mateo County, California, 94028-7522, United States
OpenStreetMap Google Maps
Phone: +1 650-854-3101

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