Montana gives cyclists three very different kinds of riding: a car-free window on Going-to-the-Sun Road each spring, the Montana stretch of the Great Divide Mountain Bike Route on gravel forest roads, and town trail networks in Whitefish, Missoula, Bozeman, Helena and Great Falls that start a few minutes from downtown. Each comes with its own rules, and the national parks enforce theirs closely.
This guide sets out the 2026 bicycle rules for Glacier and Yellowstone, what the Great Divide route looks like between the Canadian border and Helena, the public trail systems near the main towns, and where e-bikes are and are not allowed on federal land. Snow sets the calendar: high routes are usually rideable only from late June to September, while valley paths open much earlier.
Going-to-the-Sun Road in spring: the car-free weeks
Before Going-to-the-Sun Road opens fully to cars, Glacier National Park opens the plowed sections beyond the vehicle gates to hikers and cyclists. On the west side the park traditionally opens the road to cars as far as Avalanche around Mother's Day weekend in May, and riders continue from there toward Logan Pass on pavement with no traffic.
The rules, from the park's bicycling page:
- Road-crew closures apply Monday to Thursday while plowing is under way. You may ride on to the avalanche closure only when crews are not working, which in practice means Friday to Sunday.
- Avalanche-hazard closures apply at all times. The park resets their locations weekly, on Thursdays, and posts them on its road status page.
- Passing a hiker/biker closure can bring a fine of up to $5,000 and up to six months in jail.
- No shuttles run for the 2026 hiker/biker season, so plan to ride back down under your own power.
The spring window ends when the full road opens to cars: June 22 in 2026, against an average of about June 26 since 2010. Entry by bike costs $20 per person from May to October and $15 from November to April, and non-US residents aged 16 and over pay an extra $100 unless they hold an annual pass.
Summer bike hours on the Sun Road
From the day the full road opens to vehicles until September 27, the west side has afternoon bans:
| Direction | Section | No bicycles |
|---|---|---|
| Eastbound (uphill) | Apgar to Logan Pass | 12 p.m. to 6 p.m. |
| Westbound (downhill) | Logan Pass to Apgar | 3 p.m. to 6 p.m. |
In practice, start the climb from Lake McDonald early in the morning. Other park rules apply all year: ride single file on the right, pull over when four or more vehicles are stacked behind you, and show a white front light and red rear light or reflector between sunset and sunrise and in poor visibility. Bikes are not allowed on any of Glacier's hiking trails or in the backcountry. The paved path between Apgar Village and West Glacier is the easy family ride. Hiker/biker campsites cost $8 per person.
The alpine section closed for snow on October 9, 2026, so the next car-free spring season is in 2027.
Yellowstone's spring and fall bike-only roads
Yellowstone has a similar window. In spring, usually from early April (there is no set date), cyclists can ride roads that are still closed to cars, including the 49 miles from Mammoth Hot Springs to the West Entrance at West Yellowstone and 6 miles from the East Entrance toward Sylvan Pass. In 2026 the West Entrance roads opened to cars on April 17, which ended that stretch's spring season.
In fall the window runs from early November, after the roads close to public vehicles, until plowing stops in mid-November. Segments include Mammoth to the West Entrance (49 mi), Madison Junction to Old Faithful (16 mi), Tower-Roosevelt to Chittenden Road (6 mi), the East Entrance to Sylvan Pass (6 mi) and the South Entrance to West Thumb (22 mi). In 2026 the West, East and South entrance roads closed to regular vehicles on October 31. The roads are not bike-only: expect park staff, contractors and plows. Bikes are banned on backcountry trails, boardwalks and oversnow routes.
The Great Divide Mountain Bike Route in Montana
The Adventure Cycling Association's Great Divide route is 3,097.3 miles from Jasper, Alberta, to the Mexican border, and enters the United States at Roosville, Montana. Its Section 1 runs 371.1 miles from Roosville to Helena, between 2,565 and 6,840 feet, with about 28,495 feet of climbing southbound. It passes Whitefish, where Whitefish Lake State Park keeps a hike-and-bike campsite for route riders, and Seeley Lake, where the 65.4-mile Missoula Spur (rated "very challenging") branches off to Missoula. Section 2 continues 453.3 miles from Helena through Butte and south-west Montana into Idaho and Wyoming.
- Across the whole route, nearly 2,100 miles are unpaved county, Forest Service, BLM and provincial roads, about 60 miles are singletrack and about 950 miles are paved.
- Adventure Cycling suggests riding the northern Rockies between late June and late July, before the worst of fire season, and being off the route by late October; snow can arrive in late September.
- Most of the Montana section is grizzly country. Carry bear spray and follow the food storage orders on each national forest.
Town trail systems
| Town | Public trails | Notes |
|---|---|---|
| Whitefish | The Whitefish Trail | About 47 miles of non-motorised trail from 15 trailheads, run by Whitefish Legacy Partners; Whitefish Mountain Resort runs lift-served biking in summer |
| Kalispell | Lone Pine State Park | About 7.5 miles of trail; nonresidents pay $4 arriving by bike |
| Missoula | Rattlesnake National Recreation Area | More than 73 miles of trail; bikes on designated trails only, never past the wilderness boundary |
| Bozeman | Main Street to the Mountains; Hyalite Canyon | The Gallatin Valley Land Trust's town-to-foothills system is nearly 100 miles; in midsummer Hyalite's Hyalite Creek and East Fork trails alternate days between hikers and bikes, and the canyon road is closed to cars but open to bikes from April 1 to May 15 |
| Helena | Mount Helena City Park | Non-motorised trails starting a few blocks from downtown; IMBA named Helena a bronze-level Ride Center in 2013 |
| Great Falls | River's Edge Trail | Close to 60 miles of paved path and singletrack along the Missouri; avoid the dirt sections when wet |
Big Sky Resort and Discovery Ski Area near Philipsburg also run summer bike parks. One trail often filed under Montana is not: the Route of the Hiawatha rail trail lies almost entirely in Idaho. Its East Portal trailhead is just inside Montana, about 2 miles from I-90 exit 5 at Taft, and the 1.66-mile Taft Tunnel passes under the state line. Passes are sold through Lookout Pass Ski Area.
E-bike rules on federal and state land
- Glacier: e-bikes are allowed where bikes are, if the motor is under 750 watts and assists only while you pedal. The Sun Road time limits still apply.
- Yellowstone: Class 1 and Class 3 e-bikes may use the same roads, parking areas and designated routes as other bikes in the summer season.
- National forests: the Forest Service classes all e-bikes as motor vehicles. They are allowed on roads and trails open to motorised use, shown on each forest's free Motor Vehicle Use Map, unless a forest has designated a non-motorised trail for them.
- BLM land: field offices may open individual non-motorised trails to e-bikes; check with the local office before riding.
- Wilderness areas: no bicycles of any kind.
- State trust land and state parks: we found no published e-bike policy from Montana FWP for state parks, so ask the park manager; state trust land is managed separately by the DNRC.
Before you go
- Check Glacier's road status page for the current hiker/biker closure points, especially on a weekday.
- Plan Sun Road climbs to finish before noon eastbound in summer.
- Pay the park entrance fee for each rider; carry bear spray on every trail ride.
- Look up the Motor Vehicle Use Map before taking an e-bike onto a national forest.
- Pack lights, layers and rain gear: Logan Pass can be near freezing in July.
Details checked October 2026.