Feb 18, 2023 at 8:00 AM

FOURmidable 50K

298 Pacific Ave

Auburn CA, 95603


Event Facebook page

Event Twitter feed

Entry Fee $15
(Lowest or Early Registration)

Entry Fee 2 $125
(Highest or Late Registration)

Prize Money: yes


  • 13.1M
  • 50K
  • 13K
  • 35K

Type: Ultra

Starting Elevation: 1600

High Point: 1600

Percent of the course on un-paved trails: 100%

First Year of the Event: 2013

Men's Record: 2017 Max King (36) 3:32:36

Women's Record: 2018 Stephanie Howe Violett (34) 4:10:16


Come and participate in one of the most challenging 50K in the Auburn/Cool area. This event has a total accumulative climbing of over 6,000 feet in the 50K.

The name FOURmidable comes from the four major climbs along the course. The 50K runners will start by going down to the river, to then climb back up by using Cardiac hill. After the 5 mile loop runners will reach Gate 142 AS (start area); after getting the hydration and calories they need, runners will run towards the famous No Hands Bridge on their way out and climb up K2 (aka-Training hill) towards the top of Knickerbocker Canyon to then descend all the way down to the river. At which moment runners will be right on the other side of the American River canyon which can be seen from the START area. Runners will then climb up the switchbacks back to the Knickerbocker AS to then cross Knickerbocker creek on their way towards Cool AS and then follow the Western States trail towards No Hands AS and on their way up to the finish.



Past Event Dates

Held on Feb 18, 2023

Held on Feb 19, 2022

Held on Feb 14, 2021

Held on Feb 15, 2020

Held on Feb 16, 2019

Held on Feb 17, 2018

Held on Feb 18, 2017

Held on Feb 20, 2016

Held on Feb 21, 2015

Held on Feb 22, 2014

Held on Feb 23, 2013