Road Biking Routes in Boulder

Boulder, Colorado is great for anything outdoors, especially road biking. The city has a cult road cycling culture unparalleled in most other cities in North America. With lots of sunshine throughout the year, you will be hard pressed to spend a day out in Boulder without seeing somebody on a bike - yes, even in winter! Cycling in Boulder means limitless routes in varied terrain, from grueling climbs to long and scenic cross country stretches. Trust us, finding an epic road bike ride in Boulder isn’t a problem. Luckily, we have compiled a list of the best road rides in Boulder below.

What’s New in 2026

• IRONMAN 70.3 Boulder returns on 13 June 2026, and its bike course uses the roads north and east of town. Expect crowds, marshals and rolling closures that morning, so plan around it or head for a canyon climb instead. The full-distance IRONMAN Boulder has not run since 2019.
• Boulder’s dry, sunny climate keeps the roads open for most of the year, and locals get out on clear winter days. The canyons hold shade and ice longest, so Left Hand Canyon, Boulder Canyon and Flagstaff are at their best from spring through autumn, while the Peak to Peak Highway is a summer route once the high country warms up.
• The town sits at roughly 1,655 m and the canyon climbs go considerably higher, with the Peak to Peak Highway running along the Continental Divide. If you are arriving from sea level, give yourself a few days before taking on Flagstaff or Left Hand Canyon.
• Boulder Canyon on SH 119 has narrow shoulders and steady traffic, so an early start makes a real difference. For a car-free option, the Boulder Creek Trail runs right through the middle of town and links much of the city’s path network, and the Boulder County open-space roads north of town stay quiet most days.

THE BEST ROAD BIKE RIDES AROUND BOULDER, COLORADO

1. Left Hand Canyon (52.7 km, 1,094 m, 4-5h): Left Hand Canyon is one of the best road bike rides in Boulder and along the entire Colorado Front Range. Featuring a long steady climb along a shaded shoulder, it is the perfect way to spend a day out in Boulder.
2. Flagstaff Mountain (28.9 km, 1,017 m, 3-4h): Flagstaff Mountain Road is a steep and twisty mountain road that begins at the base of the iconic Boulder Flatirons. Conveniently close to downtown Boulder, and being one of the steepest roads in the area, makes this ride an experience you will never forget!
3. Jamestown (26.0 km, 387 m, 2-3h): A popular variation to the longer Left Hand Canyon, the bike ride to Jamestown takes in some of the best parts of Left Hand Canyon and continues up to a sleepy mountain town nestled in the heart of the mountains. Jamestown is a small, historic town worth a visit on its own, but combined with a great ride makes for a perfect day out in Boulder.
4. Olde Stage Rd (19.3 km, 282 m, 1.5-2.5h): Olde Stage Road is the classic introduction to hill climbing in Boulder, with a relatively short and straight forward climb up the popular Front Range road and a fun descent down the backside!
5. Lee Hill (27.3 km, 521 m, 2.5-3.5h): Lee Hill is the big brother ride to Olde Stage Road, meaning this route climbs a bit higher and for a bit longer, making it a more committing ride overall while still offering a great day in the mountains!
6. N 63rd St (27.9 km, 221 m , 2.5-3h): North 63rd St is the classic Boulder bike ride. This loop has gently rolling hills and mountain views! The nicely paved road with a generous shoulder is perfect for a stress-free day on the bike.
7. Peak to Peak Hwy (70.1 km, 1,289 m, 5-7h): The Peak to Peak Highway is a high elevation, scenic road that parallels the Continental Divide. There are multiple variations for riding the whole thing or sections of this long road; we’ve described the variation most popular with Boulder cyclists.
8. US 36 to Lyons (38.8 km, 340 m, 3-4h): US 36 to Lyons is a popular Boulder bike ride that serves as a training ground for many professional athletes; sections of this ride are a part of the official Iron Man Boulder bike course! It is for that reason that we included this ride on the Top 10 Boulder road bike rides.
9. Boulder Creek Trail (18.4 km, 77 m, 2-3h): Boulder has a vast network of wonderful bike paths throughout the entire town. Boulder Creek Trail is the most scenic and continuous of all the Boulder bike paths.
10. Boulder Canyon (47.4 km, 891 m, 4-5h): Boulder Canyon is the most scenic canyon in the area and an excellent ride, but it is not for the fainthearted. Narrow shoulders, aggressive traffic, and broken concrete make this a ride for only the diehard thrill seekers that want to challenge themselves.

Book a Cycling Tour

Boulder is a great destination for road biking, but planning a trip can be a hassle. If you want somebody else to plan your adventure, be sure to check out these Global Bike Tours. It doesn’t get much better than exploring the world on your bike! You can also browse guided tours in the United States.

Plan Your Trip

Boulder is the heart of road biking in Colorado, part of our wider road biking in the USA and road biking routes collections. For dirt, see mountain biking in Boulder, or head out on foot with our hiking routes in Boulder.

Frequently Asked Questions About Road Biking in Boulder

What is the best road bike climb in Boulder?

Flagstaff Mountain is the one most people come for, a steep, twisting climb that starts at the base of the Flatirons a few minutes from downtown. Left Hand Canyon is the other classic, a long and steady gradient along a shaded shoulder that suits a full day out. For a first climb, Olde Stage Road is the gentle introduction and Lee Hill is its bigger sibling.

Can you road bike in Boulder year-round?

Close to it. Boulder’s dry, sunny climate means locals get out on clear days right through winter, especially on the flatter roads east of town and the Boulder Creek Trail. The canyons hold shade and ice longest, so save Left Hand, Boulder Canyon and Flagstaff for spring through autumn, and leave the Peak to Peak Highway for summer.

Do you need to worry about altitude cycling in Boulder?

It is worth respecting. The town sits at roughly 1,655 m and the canyon climbs go considerably higher, so if you have flown in from sea level give yourself a few days of easy spinning before taking on Flagstaff or the Peak to Peak Highway.