USFS National Forest System Trails · San Juan National Forest · Colorado · Updated June 2026
Box Canyon Spur (USFS trail 171) is a 1.7 mi trail in San Juan National Forest, Colorado. Mountain-bike use here is accepted but discouraged in USFS data, with Class 1 e-bikes also designated.
Can I bike Box Canyon Spur?
| Use | Status | Season on record |
|---|---|---|
| Mountain bike | Accepted but discouraged | — |
| Class 1 e-bike (pedal-assist, 20 mph) | Allowed | Jun–Nov |
| Class 2 e-bike (throttle, 20 mph) | Allowed | Jun–Nov |
| Class 3 e-bike (pedal-assist, 28 mph) | Allowed | Jun–Nov |
Zooming out: across San Juan National Forest, 29% of rideable trail miles are open to mountain bikes — a Bike Access Grade of C.
Watch San Juan National Forest for access changes
Email me when USFS mountain-bike or e-bike designations change for trails in San Juan National Forest. Free, unsubscribe anytime.
About this trail
Box Canyon Spur (USFS trail 171) runs 1.7 mi through San Juan National Forest in Colorado. The figures here are pulled from the official US Forest Service trail data for San Juan National Forest, covering the trail's mileage, tread, grade band, and the bike and e-bike uses the agency lists as designated. USFS records list its surface as native material. Based on slope, this is a Easy trail (grade band +5-8%); that reflects gentle gradient and is not the same as a technical MTB difficulty rating. Note that mountain-bike use here is discouraged in USFS records — confirm with the ranger district before riding. The record additionally permits Class 1, Class 2, Class 3 e-bike use, Jun–Nov; recall that Class 1 is pedal-assist, while Class 2 adds a throttle and Class 3 a higher cutoff speed. The route is mapped as USFS Trail Class 2 on the agency's 1-to-5 development scale, where 1 is the most primitive, minimally maintained tread and 5 is the most developed. Treat this as a planning reference rather than a live conditions report, and verify any time-sensitive closure or order with the ranger district that manages San Juan National Forest.
Frequently asked questions
- Can you mountain bike on Box Canyon Spur?
- Mountain-bike use on Box Canyon Spur is discouraged in USFS records, though Class 1 e-bike use is designated. Confirm current rules with the managing ranger district.
- Are e-bikes allowed on Box Canyon Spur?
- Class 1, Class 2, Class 3 e-bikes are designated on Box Canyon Spur in the USFS data.
- How long is Box Canyon Spur?
- Box Canyon Spur measures about 1.7 mi in total, summed across its mapped National Forest System segments.
- What is the surface of Box Canyon Spur?
- USFS data records the tread surface of Box Canyon Spur as native material.
- How difficult is Box Canyon Spur?
- Its grade-based difficulty is Easy (grade band +5-8%), derived from USFS slope data. This reflects steepness, not technical mountain-bike difficulty.
How we read this data
Grade-based difficulty above is the USFS grade (route steepness), not a technical mountain-bike rating — a gentle-grade trail can still be rocky or technical, and vice versa. Bike and e-bike status come verbatim from the USFS managed-use fields for this trail; we never infer access we can't cite. See our methodology for how the dataset is built and what each field means.
Where it is
Approximate location of San Juan National Forest (USFS trail geometry isn't mapped).
Where to stay near San Juan National Forest
Find hotels, cabins, and vacation rentals near San Juan National Forest — plan your ride.
Top-rated places to stay near San Juan National Forest
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Riding San Juan National Forest?
Trail-access updates and trip ideas by email.