Embrace the Spirit of San Francisco with Hunter S. Thompson's "Fear and Loathing" Ultra Race, jointly presented by the storied Haight Ashbury Ultra Society since 1985, Zombie Runners from 2006 to 2011, and Fat Ass Runners starting in 2012. This unique event invites you to experience San Francisco's iconic landmarks on foot through a challenging yet scenic course that spans either 50 kilometers or the full marathon distance of 50 miles. The adventure begins at sunrise atop Twin Peaks, the city’s highest point, offering breathtaking views as you launch into your journey. The single-loop route takes runners through some of San Francisco's most recognizable locations, including Fisherman's Wharf, Chinatown, and Golden Gate Park, while testing your navigation skills with intentional detours and opportunities to get lost. Aid stations are minimal but strategically placed along the course: at Mile 6 near Cesar Chavez Street, Mile 14 in Japantown, Mile 20 by Coit Tower, Mile 32 around Lake Merced, and more. These stops offer a chance for runners to refuel with pastries from local bakeries like those found at the Ferry Building Marketplace or cappuccinos from North Beach cafes. For those aiming to complete the full 50 miles, reaching Mile 25 within an ambitious 4 hours and 45 minutes is crucial. If you make this cutoff time, you'll continue on for another challenging loop around Twin Peaks to hit the true mark of 50 miles. Otherwise, runners are encouraged to switch to the 50K route before heading back home. This event celebrates its commitment to community service through support for Noé Castañón's Shoes For Runners charity since 2012, providing running gear and shoes to underprivileged communities in Mexico and beyond. Join us as we honor Hunter S. Thompson’s legacy of fearless exploration and embrace the spirit of San Francisco’s rich history with this unforgettable urban ultra adventure. Volunteers are a crucial part of making this event happen; if you're interested in getting involved, please email Chihping Fu for more information.
Races Offered
50 Miler
Dec 06, 2026
straighten
Distance —
80.5K
terrain
Type —
Running
timer
07:00
50K
Dec 06, 2026
straighten
Distance —
50K
terrain
Type —
Running
timer
07:00
Weather History
These values represent the 3-year monthly averages for December in San Francisco.
thermostatTemperature
8.6° / 14.3°
wb_sunnyFeels like
6.0° / 12.3°
light_mode
Avg sunshine hours
6h 18m
water_drop
Avg rainfall
4.8 mm
ac_unit
Avg snowfall
—
air
Avg wind speed
10.0 km/h (Light breeze)
opacity
Sweat loss rate
Low
terrain
Course conditions
Firm and slightly soft
sunny
Max UV Index
Low (2.0)
humidity_mid
Humidity
85.7%
wb_twilight
Sunrise
08:17
nightlight
Sunset
17:52
About San Francisco
Learn more about the host city, San Francisco.
The centerpiece of the Bay Area, San Francisco is one of the most visited cities in the world, and with good reason. The cultural center of northern California, San Francisco is renowned for its mixture of scenic beauty and unique culture that makes it one of the most vibrant and desirable cities in the nation, if not the world.