|Great Divide Mountain Bike Route
Roosville, MT to Antelope Wells, NM
7 Map Set (2500.0 mi.)
| GPS | Overview
Great Divide Mountain Bike Route Overview Image
|1. Roosville, MT to Polaris, MT (531 mi.)||Detail
Great Divide Mountain Bike Route Section 1 Detail Image
|2. Polaris, MT to South Pass City, WY (508 mi.)||Detail
Great Divide Mountain Bike Route Section 2 Detail Image
|3. South Pass City, WY to Silverthorne, CO (405.8 mi.)||Detail
Great Divide Mountain Bike Route Section 3 Detail Image
|4. Silverthorne, CO to Platoro, CO (316.5 mi.)||Detail
Great Divide Mountain Bike Route Section 4 Detail Image
|5. Platoro, CO to Pie Town, NM (430.9 mi.)||Detail
Great Divide Mountain Bike Route Section 5 Detail Image
|6. Pie Town, NM to Antelope Wells, NM (307.8 mi.)||Detail
Great Divide Mountain Bike Route Section 6 Detail Image
|CANADA - Banff, AB to Roosville, MT (253.9 mi.)||Detail
Great Divide Mountain Bike Route Section CANADA Detail Image
The Great Divide Mountain Bike Route (GDMBR) is Adventure Cycling's premier off-pavement cycling route, crisscrossing the Continental Divide north to south. This route is defined by the word "remote." Its remoteness equates with spectacular terrain and scenery. The entire route is basically dirt-road and mountain-pass riding every day. In total, it has over 200,000 feet of elevation gain.
The route is geographically divided into five regions. The diverse nature of the regions makes for an incredible visual, sometimes spiritual experience. The route offers something different every day — whether it be riding conditions, scenery, points of interest, or folks along the way. It is a route to be enjoyed for its diversity.
A wide variety of road conditions exists along this route. Surfaces range from pavement, good gravel roads, four-wheel-drive roads, singletrack, or old railroad beds. There is an excellent opportunity to view wildlife such as bear, deer, wild horses, pronghorn antelope, eagles, osprey, sandhill cranes, and other birds and animals. The route is rich in history, with ghost towns, deserted mines, wagon routes, and old Spanish land grants. The route is near or goes through several national parks such as Glacier, Yellowstone, and Grand Teton. Temperatures tend to be chilly at night and cool to warm in the days as you are in mountainous regions most of the way. Wind really isn't a factor along the route because you spend a lot of time in the cover of trees, with the exception of the Great Basin area. Snow, hail, and afternoon thundershowers can be a factor. Getting up and riding early to avoid the afternoon thundershowers is advisable. Medical help is often a long distance off of the route, so riding within your abilities and being aware of dangers is a must. Mosquitoes are a fact of life — take repellant.
Beginning at the Canadian border and heading south to Helena, Montana, you are in the deep woods and steep mountains near Glacier National Park and the Bob Marshall Wilderness. This area is native to grizzly bear, elk, moose, mountain lion, thick woods, and has some difficult climbing. Montana is characterized by mountainous riding in tall forests with occasional dips into small towns. It is also noted for its friendly people. The capital city in Montana, Helena, has less than 40,000 people and a nice small-town feel to it. The other big town along the route is Butte, which has a definite blue-collar, mining flavor. Montana also has the toughest downhill on the route — nicknamed "thermarest hill" for all the thermarests it has eaten. Even the hardiest riders have to walk this one.
From Butte to Pinedale, Wyoming, you'll be riding through wide-open mountain valleys. The vegetation thins out into valleys with many different varieties of sage and high-elevation alpine woods. The route crosses the Continental Divide many times, and the climbing is longer with very steep sections on some of the roads. You'll see many cows. You leave Montana crossing the divide into Idaho. You are only in Idaho for 72 miles and ride along some blue-ribbon fishing streams and an old railroad bed on the west side of Yellowstone National Park. You'll cross into Wyoming between Yellowstone and Grand Teton National parks on a very scenic road with some great backcountry campsites and a genuine undeveloped hot springs. The route cuts through a corner of the Tetons before heading east up over the divide again and then down the west side of the Wind River Range. The prettiest alpine region on the whole route can be found here. Just south of Pinedale, is a stretch with the worst mosquitos on the entire route but makes for a great character builder. Farther on there's the unforgetable sensation of riding on the crest of the divide for several miles. You then hit an extremely picturesque section of high desert following the Lander cutoff — part of one of the westward wagon routes. Water is very scarce through here, so carry plenty. After dropping into the twin ghost towns of South Pass and Atlantic City, you will cross the Great Basin — a place of almost no drinkable water and no trees. Big northwest winds blow across vast open territory marked with wild horses and antelope. Rawlins, Wyoming, marks the end of the desert.
From southern Wyoming to northern New Mexico, you'll be in the Colorado Rockies. The ascents on the route stretch out to long mountainous climbs at elevations starting at 8,000 feet or above. Incredible aspen stands, huge mountains, beautiful alpine meadow flora, historical tourist towns, and a less remote wilderness setting are the characteristics of this state. Expect early evening thunderstorms and cold nighttime temperatures. The highest pass of the route is Indiana Pass, elevation 11,910 feet, in southern Colorado. Soon after crossing it, you get to see firsthand what kind of scars mining can leave on the land as you pass right through a federal Superfund site. Heading into New Mexico, the road surface deteriorates, with much more rocky riding. Here the countryside turns much drier, and water sources can be few and far between. Climbs get shorter and steeper. Geographically this region is as remote as any place in the continental United States. Mesas, cliff lines, volcanic formations, and mountain ranges that seem to pop right out of the desert floor are major visual features of this area. Many different cactus and grass varieties somehow provide habitat for small rodents, snakes, and lizards. Townspeople are right out of Old Mexico, with Spanish spoken more than English. Late-summer monsoon rains turn roads into sloppy, red clay and can fill many of the dry creek beds on the route in seconds. Roads are impassable until they dry out. This area is both historically and anthropologically dominated by the rich Native American and southwestern Spanish culture. Coming down the east side of the Gila Wilderness is a welcome relief, with water once again available as you head into Silver City, New Mexico, a place noted for learning about Anasazi culture with the Gila Cliff Dwellings National Monument north of town and a good museum at the local university. From there it is a sprint south (mostly on pavement) to the border crossing, which consists of one building on the border and nothing else for miles and miles.
Photo by Aaron Teasdale
With the exception of the Great Basin in Wyoming, you will be either gaining elevation, or descending, for the entire route. The elevations are lower in Montana — building up to the highest passes in Colorado and then tapering back off in New Mexico. However, some of the toughest climbs are in Montana and New Mexico because of the steepness and the poor road quality. And in New Mexico you'll be carrying extra food and water for the serviceless stretches.
This route can be ridden anytime from early summer to mid-fall. Be aware that snow can occur at any time along the route. If it is a heavy snow year, high-elevation roads in the north may not be open until late June or early July.
We discourage you from attempting to ride this route solo; in fact, a minimum group size of three is strongly recommended. If a rider is debilitated in the backcountry, you will want to have at least one person to stay with the injured/sick rider, and another to go for help. A growing number of backcountry travelers are carrying cellular phones for such emergency situations – but be aware that reception is still very spotty along much of the route.
Because June is typically a wet month in the northern Rockies, and often a cold one at the higher elevations, we recommend that you do not attempt to ride prior to late June or early July. High-country snowpack may prevent certain portions from being passable until then, anyway. Concerning the other end of the cycling season, plan on being off the route by mid-October at the latest. Regardless of when you strike out or how long you intend to be there, pack along raingear and cold-weather clothing. Snow or cold rain is possible any day of the year at some of the elevations encountered, and hypothermia is an ever-present possibility.
For a couple of reasons, the narrative leads you in a north-to-south direction only. First, the route was laid out going north to south and, as you’ll see, some of the downhills encountered when you’re aimed southward would be very tough to negotiate as uphills in the opposite direction. Second, for those tackling the entire 2,754-mile route, a more favorable weather window exists when riding north to south. One can begin riding in Canada in late June or early July; arrive in the high country of Colorado in August, when the route there is snow-free; and finish up in the potentially hot and dry New Mexico portions in late September/early October, when things have cooled down a bit. To do it the other way, in order to take advantage of cooler spring weather in New Mexico you’d have to leave before May 1 – meaning that you’d get to the high country of Colorado when snow still covers much of the route.
That said, even many prospective Great Divide through-riders following our recommended north-to-south strategy have been foiled. Autumn rains have been known to make extended portions of the route in New Mexico impassable for days at a time. And wildfire – what might be considered a rainstorm’s polar opposite – can also close segments of the route.
If you're in need of a shuttle to complete your Great Divide trip, download our Great Divide Shuttle Options (PDF/44k) for suggestions.
The remoteness of this route translates to long stretches of country without basic services, particularly emergency services. All services are minimal at best, except near larger towns, and cell phone coverage is only about 5 percent of the route. About one third of the overnights are characterized as undeveloped wilderness sites, and most others are Forest Service sites with pit toilets and a water source. Food sources are usually small-town establishments, convenience stores, and campground groceries with limited supplies. Towns are spaced every two to three days along most of the route. They tend to be extremely small and often have limited services. It is necessary to be flexible in what you eat. Showers, flush toilets, drinking water, and laundromats are sometimes widely spaced. It is good to have some back-country camping experience before riding the Great Divide to know how to minimally impact the land. The Great Basin in Wyoming and New Mexico both call for long-mileage days and carrying food and water for several days at a time.
You should also carry bear repellent, available at sporting goods stores in the larger towns of Canada and Montana, and become familiar with its safe and proper use. Always be bear-aware, and follow these rules when camping:
The Great Divide Mountain Bike Route is extremely hard on equipment. The weight of your gear exponentially multiplies the stress of riding steep, fast, rough downhills. Wheels, tires, and drivetrains (chains, cassettes, bottom brackets, chainrings) take a lot of abuse and might need replacing along the course of the entire route. Suspension equipment on the bicycle helps to mitigate the abusive nature of the terrain. That said, nylon pivots of some full-suspension bikes wear out extremely fast and are not recommended. Suspension seatposts, good handlebar grips, and front-suspension forks help smooth out the many miles of washboarded and chuckholed roads. Weighting a suspension fork with panniers works well, evens the weighting of the bike, and adds little extra stress to the fork. Trailers also work well and lighten the rear triangle of the bike.
Well-made camping gear is essential for the many nights of high-elevation cold, dew, and rain. A well-ventilated, free-standing, three-season tent covered by a rainfly with ample vestibule space and a "footprint" ground tarp is a must. Sleeping bags should be rated to below 20 degrees Fahrenheit, and inflatable mattresses add comfort and warmth. A lot of effort must be taken to keep your possessions dry. Pannier covers, dry bags, and plastic freezer bags all work well to keep the rain and dew off clothing and gear. Good rain gear is also essential.
A high-quality water filter is mandatory; advisably, carry one filter per person in your party. Surface water should be ingested only after running it through a good water filter.
The Great Divide Mountain Bike Route narratives, including the Canada section, are also available in text format. These files are not a substitute for the maps, only a means to customize the narrative to suit one's handlebar map case.