Twelvemile: climb Colorado’s last unpaved state highway

“There’s no way this is a Colorado State Highway,” you think, breathing deep the mountain air, rich with ponderosa. The scent is pine and vanilla cupcake. The trees? Towering, rusty-orange pillars crowned in green. Stony grey outcrops burst from the hillside. The

Photo Credit Scott Tribby

crunch of gravel under tires plays to the rhythm of your breath. You catch glimpses of the Wet Mountain Range and its rocky domes bubbling up from a forest sea. You’ve climbed 1,500 feet of gravel…and there’s more than that left to go. This segment of CO-78 is known locally as “Twelvemile”, and it is legendary. 

Twelvemile is more than a climb. It’s a time machine. 

The climbing begins after you’ve descended CO-78 into the Beulah Valley and the town of Beulah, which is its own holdout from an earlier time. At the heart of the small valley floor are open farm fields occasionally flanked by historic homesteads dating back over a century. Ascending west from Beulah, CO-78 turns from a run-of-the-mill, rural road to an unpaved gravel marvel in the mountains. It’s also a piece of living history. 

A vanishing road

As far as we know, this remote gravel segment of CO-78 is the last unpaved, state-maintained highway in Colorado. It’s a unicorn in today’s world of widening shoulders and smoothed-over edges. As a “State Highway”, you may think of speed and traffic; Twelvemile is low-traffic, rustic, and wild. Riding Twelvemile as a gravel road is an endangered experience that may not be here forever, especially in a rapidly growing state known for its ongoing roadway improvements and gravel “upgrades” to pavement. You’ll rarely ride a state highway like this — and you may never again.

A birthplace of outdoor recreation as we know it

This region isn’t just gorgeous. It’s the birthplace of modern outdoor recreation. Pueblo Mountain Park, with its classic log-and-stone architecture, was created in the 1920s with support from the City of Pueblo. Not long after, the U.S. Forest Service designated the nearby Squirrel Creek Recreation Unit…the first of its kind in the country. If you’ve ever pitched a tent in a national forest or hiked a public trail, you’re part of the movement that started right here.

Both were developed with the help of Arthur Carhart, a visionary who helped shape the idea that wild places should be for everyone — not just the wealthy. That idea lives on in Grassroots Gravel’s own mission: an epic experience that welcomes everyone.

What it’s like to ride Twelvemile: beautiful, brutal, and unapologetic

This is an experience you earn. The climb has been praised by World Tour veteran racers, bikepackers, and riders from across the country. The ride is known for the persistent and varied challenge it offers, as well as the phenomenal and plentiful spots to pause for a breath or view along the way. The terrain and texture don’t present a typical technical challenge. It’s the grade and length, not technical features, that demand your mental focus. 

The climb is punctuated with the occasional small descent and flat section. Don’t get fooled. You’re not done yet. At some points, the grade can briefly push 16%, which means you’re going to be focusing on your pedaling and position to maintain traction. And as with any hill…you’ve got to keep things under control on the descent. 

What’s the gravel like? Shockingly good, with varied sections ranging from fine champagne goodness to moderate classic gravel. 

Twelvemile: The Heart of Grassroots Gravel’s Long Course

Grassroots Gravel is based in Pueblo, CO and known for its quality and welcoming atmosphere. This year, they’re adding spice to the long course with a new twist. Twelvemile has always been the backbone of Grassroots Gravel’s long course, “The Whole”. This year, they’ve created the Solar Roast Coffee Climb: a race within a race. It’s a timed segment of “The Whole” with dedicated podiums featuring cash & coffee prizes. At the summit, Solar Roast Coffee, a Pueblo-based roaster known for the world’s only commercial solar-powered roaster, greets you with a well-earned cup…whatever pace your race.

A Race Within the Race

In the midst of “The Whole” course, the Solar Roast Coffee Climb segment begins at the climb’s base and ends at the summit, with podiums and equal awards for top 3 in each category (Women, Men, Non‑binary):

The Solar Roast Coffee Climb (and Twelvemile) by the numbers and metrics

• Distance: 11 miles
• Starting Elevation: 6,275 feet above sea level
• Summit Elevation: 9,585 feet above sea level
• Total Gain: ~ 3,400 feet
• Average Grade: 5.7%
• Approximate Max Grade: 16%

When to ride it

The best time to ride it: During Grassroots Gravel (every October)

• Registration for Grassroots Gravel sells out every year — long before event week. And this is the only time Twelvemile becomes a fully supported race segment, with aid at the base and coffee at the top. If you want to race Colorado’s last wild climb, this is your shot. Learn more and register

Most of the year…except the heaviest snow months of winter.

• Twelvemile is a public road and can be ridden whenever you want. It’s typically best in the fall (again…see above re: Grassroots Gravel), but is a great ride most of the year. Summer can get hot, and you’ll want to keep afternoon thunderstorms in mind. Winter can be passable depending on weather and snow conditions. With a summit over 9,500 feet above sea level, its significant gain and length, this climb should be respected. View the segment here.

Whether you’re chasing a podium or chasing a moment in the mountains, Twelvemile delivers. It’s beautiful, brutal, and rare. And it’s waiting.