Betasso Preserve
Betasso Preserve is a Boulder County Parks & Open Space foothills preserve above Boulder Canyon, best known for the 3.3-mile Canyon Loop. It's a mountain-biking favorite, free to visit, dogs on leash, with bikes prohibited on Wednesdays and Saturdays so hikers and runners get quiet trails.
Outdoor Boulder › Destinations › Betasso Preserve
Betasso Preserve quick facts
| Location | Western foothills above Boulder Canyon, off Sugarloaf Road. Managed by Boulder County Parks & Open Space, not the City of Boulder. |
|---|---|
| Distance and loops | The Canyon Loop is 3.3 miles; the Benjamin Loop adds 2.4 miles. Shorter connectors (Betasso Link, Loop Link, Fourmile Link) let you build a longer or shorter day. |
| Elevation | The trails sit high in the foothills, running roughly between 6,200 and 6,500 feet. |
| Difficulty | Moderate to difficult. The Canyon Loop rolls with steady ups and downs rather than one big climb. |
| Bike days and direction | Bikes are prohibited on the loop trails every Wednesday and Saturday. On the days bikes are allowed, they ride a single designated direction that the county reverses on a schedule, so follow the posted arrows. |
| Dogs | Dogs are allowed but must be on leash. This is Boulder County Open Space, so the OSMP Voice and Sight tag does not apply here. |
| Fee | Free. There's no entrance or parking fee. |
| Parking | Two trailheads: the main Betasso trailhead and the Bummers Rock lot. Combined capacity is small (about 44 vehicles), so it fills on nice weekends. |
| Best season | Spring through fall. At this elevation the tread can stay muddy or snowpacked after storms, so let it dry out, and start early on warm summer days. |
Betasso Preserve at a glance
Betasso Preserve sits in the western foothills above Boulder Canyon, reached by climbing Sugarloaf Road off Boulder Canyon Drive. It's a Boulder County Parks & Open Space property, which matters for the rules: this is county open space, not a City of Boulder park, so the fees, dog rules, and bike schedule are set by the county. What you get is a high, breezy stretch of ponderosa forest and meadow with mountain views one way and the golden plains the other, and a set of flowing loops that runners and mountain bikers both love.
Mountain biking at Betasso: the bike days and direction
Betasso is one of Boulder's classic mountain-bike rides, and the county manages it carefully so bikes, hikers, and horses aren't fighting for the same singletrack. The big rule to know: bikes are prohibited on the loop trails every Wednesday and Saturday. Those two days belong to people on foot and on horseback. On every other day bikes are welcome, but the loops are directional, meaning you ride one designated way around, and the county reverses that direction on a schedule. Don't assume which way it runs today, just follow the posted arrows at the trailhead and junctions. E-bikes are not allowed at all.
The Canyon Loop and Benjamin Loop
The heart of Betasso is the Canyon Loop, 3.3 miles rated moderate to difficult. It rolls through forest and open meadow with steady short climbs and descents rather than one long grind, which is what makes it such a good flow ride and a fun run. To make a bigger day, add the Benjamin Loop, another 2.4 miles, or stitch the two together with the connector trails (Betasso Link, Loop Link, and Fourmile Link). For a short leg-stretch with a view instead, the Bummers Rock trail is a brief out-and-back to a rocky overlook.
Hiking and trail running
Hikers and trail runners are welcome any day, but Wednesdays and Saturdays are the sweet spot, since that's when bikes are off the loops and the trails are calm. The Canyon Loop makes a satisfying few-mile run or hike with rolling terrain and long views, and the footing is generally good singletrack. At this elevation, roughly 6,200 to 6,500 feet, mornings stay cool and afternoon storms can build in summer, so plan to be off exposed sections if the sky turns.
Dogs at Betasso Preserve
Dogs are allowed, and they have to be on leash the whole time. Because Betasso is Boulder County Open Space rather than City of Boulder OSMP land, the Voice and Sight tag that lets a dog go off-leash on certain city trails does not apply here. Leash rules are enforced, it's a day-use preserve with no camping, and cleaning up after your dog keeps the trails open to them.
Parking, fees, and getting there
Betasso is free, with no entrance or parking fee. There are two trailheads, the main Betasso trailhead and the Bummers Rock lot, and combined they only hold around 44 vehicles, so the preserve's popularity is its own catch: on a bluebird weekend the lots fill early. Come first thing in the morning or later in the afternoon, and if you're towing a horse trailer, use the Bummers Rock trailhead. The access road climbs and narrows, so take it easy on the way up.
Best season and time to go
Spring through fall is prime, with fall especially pretty as the meadows turn. Up here the tread can hold mud or snow after a storm, so give it a day or two to dry rather than rutting it up. If you want the trails to yourself, aim for a Wednesday or Saturday morning when bikes are off the loops, and either way, an early start beats both the crowds and the summer afternoon thunderstorms.
Nearby trails and guides
- All hikes in Boulder: the full hiking hub, sorted by difficulty.
- Walker Ranch: a rugged, bigger foothills loop farther up the canyons.
- Mountain biking in Boulder: our biking guide is on the way, with Betasso front and center.
Recommended nearby
A few local spots we'd point a Betasso day toward.
[CLIENT SLOT: featured bike shop near Betasso Preserve]
[One honest line: where to rent or tune a mountain bike before the ride.]
[CLIENT SLOT: featured cafe near Betasso Preserve]
[One honest line: coffee or a bite on the way up or down the canyon.]
[CLIENT SLOT: featured outdoor shop near Betasso Preserve]
[One honest line: trail snacks, tubes, or layers for the foothills.]
Betasso Preserve FAQ
What days is Betasso Preserve closed to bikes?
Bikes are prohibited on the loop trails every Wednesday and Saturday. Those two days are set aside for hikers, trail runners, and horses, so the trails are quieter and there's no bike traffic to watch for. On all other days bikes are welcome on the designated trails.
Are dogs allowed at Betasso Preserve?
Yes, dogs are allowed, but they must be on leash at all times. Betasso is a Boulder County Parks & Open Space property, so the City of Boulder OSMP Voice and Sight tag that works on some foothill trails does not apply here. Leash rules are enforced, and it's day use only.
How long is the Canyon Loop at Betasso Preserve?
The Canyon Loop is 3.3 miles and is rated moderate to difficult. It's the classic Betasso route for both trail runners and mountain bikers. You can extend the day by adding the 2.4-mile Benjamin Loop, or shorten it using the connector trails.
Where do you park at Betasso Preserve?
There are two trailheads: the main Betasso trailhead and the Bummers Rock lot. Between them the parking is limited (roughly 44 vehicles total), and there's no fee. On sunny weekends the lots fill early, so come first thing in the morning or later in the afternoon. If you're towing a horse trailer, use the Bummers Rock trailhead.
Is Betasso Preserve better for hiking or mountain biking?
It's a genuine favorite for both, which is exactly why the county splits the week. Mountain bikers love the flowing, directional Canyon and Benjamin loops on the days bikes are allowed. Hikers and trail runners get the trails to themselves on Wednesdays and Saturdays, when bikes are prohibited. Pick your day around which experience you want.
Sources
Facts on this page are drawn from these authoritative sources: