August 9, 2025
Come Run, Come All to Dirt Circus Boulder!
The Dirt Circus is coming to Boulder, Colorado. Dirt Circus is a series of free community events organized by UltraSignup to celebrate local races, and race directors. We are bringing together the local running community to share everything we love about trail running. The one-day festival will highlight local races, run clubs, brands, and other local businesses. The event includes a social run, food, a raffle with tons of prizes, camaraderie, and so much more. Come and join us under the big top.For information on Dirt Circus events in other cities check out dirtcircus.ultrasignup.com + join our online community on Facebook!
Local Store Partner
In Partnership With:
This event is possible because of the local partnership of Runners Roost in Boulder. Stop on in for all the running shoes, apparel, and other gear you could need.
Race Directors & Vendors
Dirt Circus is a party to bring together the whole running community, not just runners, but also race companies, coaches, nutritionists, and running brands. See below for some of the partners who will join us in San Luis Obispo!
Race Companies, Local Partners & Brands
Are you a race company or other local run business that wants to be a part of the event? Fill out this form, we'd love to have you.
Race Companies
Local Partners & Brands
Onsite Vendors
Event Details
Saturday August 9, 2025
7:15am - Group Run Check-in
Give yourself time to check in, mingle, demo shoes, and get ready to run!
Swag Bags:
All participants receive a sweet UltraSignup branded SILO "Shoe Bag Lite" filled with nutrition products from Skratch Labs, “Run Atomic Lite” socks from Sidas, Yellowbird hot sauce and more! (over $40 in value!)
8:00am - Group Run Starts
Enjoy a casual 4.5 mile or longer 7.1 mile run with friends from the local run community!
8:30am-9:30am - Return from Group Run for the Festivities!
9:00am - Drinks & Food available
9:30am-12:00pm - Raffle & Social
We'll have brand booths and tables set up around when you return from your run, whatever distance you chose. Talk to race directors, learn about local races, mingle with friends, learn about running shoes and apparel products, and maybe test out some hydration and nutrition brands!
Preorder Your Original Dirt Circus T-Shirt!
Each city on the tour gets its own exclusive design—only available for purchase during registration! Don’t miss out on the Boulder edition, with preorders closing Sunday, July 25, 2025.
Plus, explore even more Dirt Circus and UltraSignup gear available for purchase onsite. And perhaps you'll score some swag from our partners in the free raffle!
What is Dirt Circus?
Did you know that there are thousands of small local trail running events across the United States each year?
Our goal is to connect runners with races and with one another, to highlight race directors, running stores, coaches, and the other local businesses that make up the fabric of our trail running community. The best way we know how to do that is by going for a run together. This sport is a little wild and we like it that way, so come join the Dirt Circus with us.
Meet with race directors, find your next event, run with friends, win prizes and more. Think of it as a live and in-person version of ultrasignup.com, but even more fun.
Why a Circus? Once upon a time, ultrarunning looked a little different. The sport has its roots in pedestrianism, where people would gather under the big top and walk and run for sport. Bets were made, the limits were pushed, and popularity soared. So come entertain yourselves with us, under the metaphorical big top.
Route
UltraSignup Store
Shop UltraSignup gear and apparel in the UltraSignup Store.
Event's current local time: 4:05 PM MT
