Meet the Gravel Bike Adventures duo, Laura and Rose! Two women all about finding adventure and encouraging others get out and explore by helping them feel informed, included and confident on their next bike adventure. Laura and Rose curated four of their favorite gravel routes of all time to share with the Machines community! Route 02 is 4 Mile Canyon and Switzerland Trail, one of their favorite gravel routes in Boulder, CO. Stay tuned for their next adventure, and be sure to save these routes for the next time you're looking for a fun adventure! 

If you are looking for a gravel biking playground, Boulder, Colorado is incredible! Although Gravel Bike Adventures is based in Denver, CO, Boulder still feels like part of our “backyard” since it is only a 30 minute drive. If we had to pick one route among the MANY great rides in the Boulder area, this is one of our favorites.

The route is a 51.4-mile mixed-surface gravel ride that departs from the city of Boulder. Once you start, you’ll quickly forget you are anywhere near a city. Biking up paved Sunshine Canyon will get you warmed up quickly and then you’ll continue to steadily climb on the beautiful and remote dirt road in Four Mile Canyon which is right alongside the Four Mile Creek. (The first 4 miles of Four Mile Canyon is paved but the road continues for another six or so miles which is a bit confusing given its name.)

Next you’ll go up and across a technically challenging rocky jeep trail called the Switzerland Trail. You’ll have to pay a lot of attention to the rugged road surface since there are rocks and holes to dodge and there are steep drop offs on one side, but don’t forget to stop and take in the breath-taking views of the Continental Divide in this section!

Gold Hill Road and Sawmill Road are steep but non-technical dirt descents and then you'll have fun picking up speed as you come down miles of smooth pavement in Left Hand Canyon. The ride finishes on flatter dirt roads and trails through Boulder.

HIGHS:

  • Holy smokes, Boulder brings it again! This route highlights the typical joys of gravel riding in Boulder: limited cars, great views, tons of different surfaces, challenging climbs, and animal sightings.

  • Four Mile Canyon Road is really terrific. It is a great smooth and fast dirt road with quaint areas along the way. (Do they qualify as towns??!!) The atmosphere of Four Mile Canyon feels like a funky and fabulous combination of Europe, the Wild West and Yosemite!

  • We have done this route a few times now, and it felt good to conquer the technical sections on the Switzerland Trail with more confidence

  • Boulder had a few late-season snows, but we were pleasantly surprised to find that all the high-elevation roads were completely snow-free as of May, 10th 2020.

LOWS:

  • Switzerland Trail is generally very quiet and all of the Jeeps we encountered were courteous when they passed. We did not find the same when it came to the ATVs and dirt bike drivers. They sped past at alarming speeds and threw a lot of dust in the air! 

  • Crossing busy Highway 36 to get to Neva road is a bit sketchy. We had to wait quite a while to find a break in traffic in order to safely cross.

DO THIS RIDE IF: you are near Boulder, CO and you want a long climb on mixed road surfaces that is nearly devoid of cars, features amazing views of the Continental Divide, and has some technical challenges on rocky jeep trails. You'll earn the views at the top, and enjoy a smooth, fun and fast downhill on Left Hand Canyon.

TAKEAWAYS:

  • If you are willing to do a long tough climb, you will be rewarded with plenty of solitude and can escape the more crowded roads below.
  • It has been fun to learn how to best do gravel biking adventures. We've learned to watch the weather apps, plan our route and have exit strategies in case the route is particularly exhausting or something happens to our bikes. We also look at the elevation profile and when parts of our route include dotted lines instead of clear gravel or paved roads on www.coloradogravelroads.com, we do a little more research to understand what the terrain and technical biking may be.

  • When we are exploring new routes, having the security of GPS on our Wahoo Element is critical because it has the route pre-loaded and all we have to do is follow the dotted line. It allows us to relax, enjoy the ride and know that we can’t get (too) lost!

OTHER NOTES:

  • There is still a little bit of construction on the paved part of Four Mile Canyon but it is no longer down to one way traffic with lights (As of May 2020). The Switzerland Trail is pretty rocky and rugged! We most recently rode this route with 700x35cm Panaracer Gravelking SK+ Tires (set up tubeless and pumped to 40 psi) and had no problems but we could have been a little more comfortable on a slightly wider tire. 

  • After you depart the city of Boulder, there are a few places along the way to stop for bathrooms. (There are bathrooms at the Mount Sanitas Trailhead off of Sunshine Canyon and Buckingham Picnic Area off of Left Hand Canyon.) Be prepared to carry what you will need to keep you going in terms of water and food.

Driving Directions to the Start 

We parked near the The Sports Garage bike shop in Boulder where there is plenty of easy street parking.