We had done this Boulder to Carter Lake route back in December 2018, but didn’t love a few of the busy roads on the return route.
In 2020, we posted a new and improved revised route.
We recently re-road this in Spring of 2025 and it was just as delightful as it was five years ago.
The majority of the dirt roads from Boulder to Carter Lake were hard packed, non-technical and in great riding condition.
When we planned this route, we were nervous about the traffic on Highway 66 but it had a great shoulder and had lots of other cyclists.
Yes, when we rode this in the winter, it means everything is brown, but this ride felt quite beautiful with a variety of different lakes along the route. We saw so many animals, we lost count (a bald eagle, bluebirds, chickens, cows, horses, lamas, deer, cute piggies…)!!
When we rode this on Easter Day, two days after an April snow storm. Roads were tacky, fields were getting green, trees were flowering and the air smelled like Spring.
It’s a fairly rural route with few places to stop and refuel between where we started and Carter Lake (so make sure you have enough water and snacks to keep you going).
A few of the dirt roads were muddy/slushy for us in February. If you don’t want to get really dirty, give it a few days to dry out between snow storms.
Do this ride if you want the speed, feel and long distance mileage of a road ride, but with less traffic.
We found unlocked public bathrooms at the Carter Lake South Shore Campground (which was our turn-around point).
There is one very bike friendly convenience store with bathrooms to stop at in Hygiene called the Mountain Fountain. However, you don’t get there till about mile 45 in the route (Hygiene Road and 75th).
There is also now a Cafe across the street from the Mountain Foutain, called Cafe Felix and it had top notch pastries and coffee. We highly recommend the espresso tonic on a warm day!
Interested in other winter gravel routes? Check out this blog post for a few others!
We parked and started at the Lefthand Trailhead parking lot.
Laura & Rose
Laura Karpinski and Rose Barcklow are the creators of Gravel Bike Adventures. Click on the About page to learn more about them.
