Lake Chabot Trail Run

APR
11
2026
Challenge yourself on scenic Lake Chabot trails April 11, 2026 in Castro Valley with distances from 8K to 50K plus a free kids dash. Looped, well marked courses offer big climbs, frequent aid stations and finisher medals for all.
Sat 11 Apr 2026
50 kilometers Marathon 30 kilometers Half Marathon 8 kilometers

Always double-check with the organizer's website! This page may contain affiliate links.

Event overview

The SPASM Lake Chabot Trail Run takes place on April 11, 2026 in Castro Valley, CA at Lake Chabot Regional Park - Marina. The event offers the following distances:

  • 8K
  • Half Marathon
  • 30K
  • Marathon
  • 50K
  • Kid's Run (6yo & younger, 50 yd dash) - free

Course and markings

The course starts at the Marina and circles Lake Chabot and the surrounding hills. Loops are color coded: the 8K is the yellow loop, the half marathon is the pink loop, the 30K is pink plus yellow, the marathon is the pink loop twice, and the 50K is the marathon plus the 8K. The route is marked with ribbon about every 200 yards; polka-dot flagging indicates turns and blue ribbons mark wrong-way junctions. Headphones are allowed on dirt-road sections only and are not permitted on single-track trail, when crossing paved roads, or when receiving aid.

Elevation gains and surface composition by distance:

  • 8K: elevation gain 380 ft; single track 16%, dirt road 12%, asphalt 72%.
  • Half Marathon: elevation gain 1,450 ft; single track 14%, dirt road 60%, asphalt 26%.
  • 30K: elevation gain 1,830 ft; single track 14%, dirt road 48%, asphalt 38%.
  • Marathon: elevation gain 2,900 ft; single track 14%, dirt road 60%, asphalt 26%.
  • 50K: elevation gain 3,280 ft; single track 14%, dirt road 53%, asphalt 33%.

Logistics, aid, and awards

Check-in and bib/shirt pickup occur on race day; participants are asked to arrive about 45 minutes before their event. Parking is $5 per vehicle. Drop bags are allowed for the 30K, marathon, and 50K at the start/finish. All events have an 8.5 hour time limit; the marathon and 50K include a mid-course cut-off at the 13-mile point.

Fully stocked aid stations are placed every 4 to 5 miles with fruit, salty snacks, candy, water, and Skratch electrolyte drink. Runners are advised to carry at least 20 oz. of water between aid stations. The event is cupless; participants should bring their own fluid container. T-shirts are provided to pre-registered runners, all finishers receive a custom medal, and 50K finishers receive a custom coaster. Overall top three finishers in each distance receive awards and race credits. Visit the organization's website for the most recent information.

50 km
50k
Marathon
Marathon
30 km
30k
Half Marathon
Half Marathon
8 km
Kid's Run (6yo & Younger, 50yd Dash) - Free!