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  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
  • Top 10 in America – USA Today
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Boulder marathon

9.27.26

COLORADO’S PREMIER FALL EVENT

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A boutique marathon experience with big-city energy + amenities tucked away in the foothills of the Rockies

why

Bolderthon?

It’s Boulder.

Run through the endurance capital of the world — where Olympians train, mountains frame every mile, and fall turns the city into a postcard.

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The Views

Big city energy, small-town charm. Picture mountain backdrops, city buzz, fall folfoahe in Colorado and an electric finish line at the foothills of the Rockies you’ll never forget.

This isn’t a course. It’s a highlight reel.

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Lululemon for All

Every finisher gets an exclusive, limited-edition lululemon Metal Vent Long Sleeve. ($88 value. Yours to earn.)

Not swag. A statement piece.

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Sustainable

Boulderthon firsts in sustainability and innovation firsts: First race with 100% hemp bibs in 5K 100% recycled medals Designed to be lighter on the planet — and bigger on impact

Good for you. Better for the planet.

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Tech-Powered, Community-Designed

DESIGNED BY RUNNERS. POWERED BY TECH.

Personalized race insights. Smart tracking. Custom recaps. A community-designed medal you’ll actually keep.

Your race. Your data. Your story.

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The Vibes

THE PARTY STARTS AT THE FINISH.

Epic after-party. Outdoor expo on Pearl Street in the heart of the city. Live music, brands, community, energy.

“Boulderthon has the best expo I’ve ever been to.” — Dakota

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choose your

DISTANCE

Boulderthon is a top-rated marathon event in the United States, held annually in Boulder, Colorado. Recognized by Runner’s World, USA TODAY, and Active as one of the best and most beautiful races, it attracts runners from all 50 states and around the world.

2026

Half Marathon

10K

5K

KIDS RUN

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A RACE FOR
EVERY RUNNER

Every age. Every ability. Every reason to run.

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Race day INCLUSIONS

Fuel

Precision Fuel & Hydration stations every two miles.

Energy

Live music and community-powered cheer zones throughout the course.

Connection

Near real-time runner tracking with mid-race audio cheers.

Celebrate

You crushed it. Get AI-powered race recaps and near real-time photos, powered by Laurel.

Testimonial

“Community events like Boulderthon offer a unique opportunity to enrich the lives of locals, and to invite more people from around the country and the world to see why we love our home here at the foot of the Flatirons,” said Boulder Mayor Aaron Brocket. “Local businesses see a boost, visitors leave feeling excited about their experience, and that creates benefits for our city that last a lifetime.”

Mayor Aaron Brockett

City of Boulder

“Boulderthon is a strategic asset for the City of Boulder and one of our most important annual events. In only its fifth year, Boulderthon now drives nearly $23 million in economic impact – supporting thousands of jobs and generating meaningful revenue for our hotels, restaurants, retailers, and small businesses. We are proud to welcome runners, fans, and community members from Boulder and around the world, and to recognize the vibrancy, economic vitality, and community benefit this annual event delivers to our city.”

John Tayer

CEO of Boulder Chamber of Commerce
“Having Pizzeria Alberico and Frasca right at the start line of Boulderthon, it’s been incredible to see how much this race has positively impacted Boulder in just a few short years. We feel the energy building as early as Friday, with runners and visitors coming into town ahead of the Sunday race, and that momentum carries through the entire weekend. Sunday and even Sunday night are especially strong with people coming out celebrating, dining, and supporting local businesses. What’s typically a quieter fall weekend has become vibrant and full of life. From increased foot traffic to an overall elevated atmosphere, Boulderthon has been a huge asset for our restaurants and for the city as a whole.”

Bobby Stuckey

Co-Founder Frasca & Pizzeria Alberico, The Julia Child Award Recipient for 2025 Bobby Stuckey … award-winning Master Sommelier, restaurateur, winemaker and cookbook author
“Boulderthon consistently brings great energy and foot traffic to Avanti and race weekend is always a strong one for our business. Beyond the sales impact, it’s an incredible community event that brings together locals, visitors and runners of all backgrounds in a way that feels uniquely Boulder.”

Hayley Edmisten

Director of Marketing, Avanti Food & Beverage
Pizza Colore sees about a 15% increase in business for the weekend that the Boulderthon is taking place. It is always a fun event that adds a nice economic boost to the area.

Hayley Edmisten

RUN GREEN RACE STRONG

Sustainable race bib

Our race bibs are made from industrial hemp, one of the world’s most sustainable, recyclable, and 100% biodegradable materials.

90,000 cups saved from landfills

We anticipate keeping 90,000 cups out of landfills this year! We’ll have both Hiccup reusable cups and compostable cups along the course.

Infinitely recyclable hydration

Did you know that aluminum is infinitely recyclable? We’ll have water in aluminum cans at the finish line.

A PLACE LIKE NOWHERE ELSE

Feel on top of the world!

Boulder is a world-class destination offering 300 days of sunshine and endless recreation, shopping, dining, cultural and entertainment choices. It’s no wonder National Geographic named Boulder the Happiest City in America.

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Run Boulder.
Run Boulderthon.

Join thousands of runners from across the country and around the world for a race experience that combines performance, beauty, and community.

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195
DAYS

:

22
HOURS

:

07
MINUTES

:

12
SECOND