Niwot’s Challenge is a very difficult, grass-roots, ultramarathon in Colorado’s Front 11147089_796942100402340_1305977973634935207_nRange. It is modeled after the arduous Barkley Marathons in Tennessee and the historic More and More Difficult 50K in New Hampshire. Much of the information for this event is kept secret until event week. This is done for a variety of reasons pertaining to the safety of the events participants and for the preservation of the event. If you want to know more.. you’ll just have to sign up.

April 27, 2019

Can’t tell ya.. unless you sign up.
We’ll just tell ya it’ll be unforgiving terrain in the Front Range West of Denver.


Runners will travel on dirt roads, trails, and via bushwhack/off-trail. Successful completion of the course will be achieved when a runner has travelled the course, identically to how it’s been laid out, and retrieves a page from each of the books hidden on the course.


Distance: ~45 Miles
Elevation: +19,000′ / -19,000′
Time Limit: 30 Hours
Aid: Very Limited – Runners must carry all necessary gear for entirety of the event.


Distance: ~90 Miles
Elevation: +38,000′ / -38,000′
Time Limit: 60 Hours
Aid: Very Limited – Runners must carry all necessary gear for entirety of the event.


No more than 30 runners will be selected to run in this event (Strict)

Entry Fee: Donation Based – Not Required

If you would like to run in Niwot’s Challenge, follow these directions carefully…

  • Applications will be accepted starting at Midnight on Monday, January 21st thru Noon on Wednesday, January 23rd. Only those who apply during this period are given preference of potential acceptance.
  • Applicant’s must send an e-mail to with the following information
    • Your Name
    • Your Age
    • Town/State
    • Best and Worst 50 Mile Time
    • If no previous 50 Miler Completed, you must submit a short essay stating why you should be admitted to run
    • The total number of ultras you’ve completed
    • Your Spirit Animal/Totem Animal

The field will be selected on Thursday, January 24th and notified ASAP.

• We will accept the first 5 Chiefs to apply
• We will accept 15 returning Nitwits, with no finishes, from previous years
• We will then accept 10 virgin applicants

Should we not have 30 total applicants…
• We will fill the field using the equation above
• We will then accept all remaining Chiefs applicants
• We will then alternate, 1 and 1, between returning Nitwits and Virgin Applicants until full
• We will accept applicants after April 23rd, first come first served, until full

Should we have more than 30 applicants, or once we reach 30 participants…
• The event will be filled as first listed above (top section), then the second section listed above
• A wait list will be implemented by order of application received

We reserve the right to refuse entry of ANY applicant without providing an explanation for doing so. Typically, we will only deny entry due to lack of experience or fear of runner safety. This is a graduate level event and participants are expected to have considerable ultra or adventure racing experience that proves their ability to take on this challenge safely. 


All runners will be known on race weekend by their Spirit/Totem Animal. Only those who finish the Niwot’s Challenge will be given a suitable Chief name differentiating them from all other comers. Those who complete the Niwot’s Double will reach Deity level.

Information pertaining to the challenge will be issued, electronically, to runners during the week leading up to the event.
This information includes a course map, aid station location, aid and crew access point(s), additional rules, and start time of the event. This will provide runners with ample time to assemble their course maps and other needs for the event.


Years Held: 2013, 2014, 2015, 2016, 2018

Official CHIEF Finishers: Brandt Ketterer (2x – 2015, 2016), Adam Harmon (2x – 2015, 2016), Micah Morgan (2016), Todd Salzer (2016), Katie Ferrington (2016), Erik Sanders (2016), Ryan Ognibene (2016), Cory Linfield* (2016), Christopher Knott* (2016), Julian Smith (2016)

WARNING: This is NOT a run for beginners or whiners. This is an arduous event which includes a large number of off-trail miles. Participants are fully expected to be able to navigate using a map and/or compass; or by following another registered participant who can. All participants must fully understand that aid is limited, they are for the most part on their own, and they are expected to make S.M.A.R.T. decisions based on their individual limitations. No GPS is allowed on the course. Phones are permitted for emergency use ONLY.
* Indicates finishing a modified course due to weather