-->
runsignup.com

Bad Bass

calendar_today 24 Jul, 2027

directions_run Running

language Official Website

sell $55.00 – $100.00

Bad Bass

About the Event

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 24th 2027! 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!

Races Offered

Half Marathon Hiker

Jul 24, 2027

straighten

Distance — 21.2K

terrain

Type — Running

timer

07:30

sell

$100.00

Virtual

Jul 24, 2027

straighten

Distance — 21.1K

terrain

Type — Running

timer

07:30

sell

$55.00

HALF MARATHON

Jul 24, 2027

straighten

Distance — 21.2K

terrain

Type — Running

timer

08:30

sell

$90.00

10K

Jul 24, 2027

straighten

Distance — 10.3K

terrain

Type — Running

timer

08:55

sell

$72.00

5K

Jul 24, 2027

straighten

Distance — 5.4K

terrain

Type — Running

timer

09:10

sell

$63.00

Weather History

These values represent the 3-year monthly averages for July in Castro Valley.

thermostat Temperature
13.2° / 22.3°
wb_sunny Feels like
12.1° / 19.9°
light_mode Avg sunshine hours
12h 21m
water_drop Avg rainfall
0.1 mm
ac_unit Avg snowfall
—
air Avg wind speed
11.0 km/h (Light breeze)
opacity Sweat loss rate
Moderate
terrain Course conditions
Firm and slightly soft
sunny Max UV Index
Very High (8.0)
humidity_mid Humidity
75.4%
wb_twilight Sunrise
05:59
nightlight Sunset
20:27

About Castro Valley

Learn more about the host city, Castro Valley.

Scenic view of

Castro Valley is a census-designated place (CDP) in Alameda County, California, United States. At the 2020 census, it was the fourth most populous unincorporated area in California. The population was 66,441 at the 2020 census.

Read more launch

Hotels & Places to Stay

Things to Do Nearby

Tours and activities near Castro Valley, powered by Viator.

Loading nearby tours and activities…

Runner Reviews

Read what other athletes have to say about their experience at the Bad Bass.

No reviews yet

Be the first to share your experience with the community!

Suggest an edit

Spotted an error or missing detail about the Bad Bass? Help us improve.

Nearby Races

Explore other exciting events happening in this same region.

Lake Chabot Trail Run

Lake Chabot Trail Run

location_on Castro Valley, California, US

calendar_today Nov 07, 2026

Oakland Hills Trail Run

Oakland Hills Trail Run

location_on Oakland, California, US

calendar_today Oct 24, 2026

The 2026 Run for Education

The 2026 Run for Education

location_on San Ramon, California, US

calendar_today Oct 11, 2026

2026 St Benedict's Fun Run

2026 St Benedict's Fun Run

location_on Smyrna, California, US

calendar_today Oct 17, 2026

Recommended for You

Hand-picked events we think you’ll love.

Claim the Rock Invitational

Oct 05, 2026

Claim the Rock Invitational

Mason Middle School CC Meet

Oct 05, 2026

Mason Middle School CC Meet

FSRC Self Defense Class

Oct 05, 2026

FSRC Self Defense Class

Thanks to Tristar Martial Arts for once again offering to provide a self defense class to members of the Frederick Stee…

Read more
The Great Escape

Oct 05, 2026

The Great Escape

🏴‍☠️ THE GREAT ESCAPE Hunt for the Cursed Treasure | 60-Mile Virtual Run/Walk Adventure A mysterious map has resurfaced…

Read more

Get race deals & updates

Subscribe to our newsletter for curated race picks and discounts.