Great Rift Dirt Tour

Located in present-day South Central Idaho on the Snake River Plain and Columbia Plateau, the Great Rift Dirt Tour circumnavigates and passes within the 750,000-acre Craters of the Moon National Monument & Preserve. Within this protected landscape lies The Great Rift, a fissure in the earth’s crust spanning 52 miles north and south, and known to be the most extensive, recent, and deepest volcanic rift system in the continental United States.

This unique, overland bikepacking adventure around a volcanic rift zone passes by cinder cones, around expansive lava flows, caves, chasms, blowouts, and buttes. Despite the lack of climbing and elevation on the route, these features and terrain can make the riding very rugged and slow-going at times. Don’t underestimate the low elevation per mile thinking the route can be fast (sub 3 days is a real challenge!). Almost 75% of the route consists of primitive doubletrack, 4×4 trails and roads, with 83% of the route being unpaved and natural surfaces comprised of dirt, sand, rough gravel and lava rock. The route doesn’t take the most direct path through the Craters of the Moon Preserve and Monument, but it does take a path that is both interesting and engaging, encouraging the rider to slow down and take in their surroundings.

Starting in the southeast corner of the CRMO Preserve on the BLM boundary, 5.5 miles before a geological feature called Kings Bowl, one of the most defining features of the Great Rift. This can be a good place to start as well, but requires a high-clearance 4×4 vehicle to drive into. Riders are immediately immersed in the expansive high desert as they meander up and down, around and through the wide open plains of sagebrush and lava flows. Features like caves, cabin ruins, big buttes to camp and explore in, unique lava rock formations, singing and swooping birds, lizards bolting across the path and pronghorn herds bounding in the distance help the days go by quickly.

Don’t miss these highlights and opportunities:

• Camping inside craters & buttes
• Star gazing in some of the darkest night skies remaining in the continental United States (designated International Dark Sky Park).
• Exploring the lava flows, tree molds, and cinder cones in the Craters of the Moon National Monument.
• Stashing the bike at the Tree Molds trailhead and hiking into the Craters of the Moon Monument and Backcountry Wilderness area to camp for the night
• Meandering through hundreds of miles of double-track that no one knows about or takes the time to explore through the Craters of the Moon Preserve.
• Watching herds of pronghorn float through the tall sage & flowing grasses, hearing the songs of the numerous birds who migrate, nest, and thrive in these skies, and noticing an abundance of “rare” reptiles seldom seen in Idaho scamper across the trail and hideout in the sagebrush and grasses.
• The blooming sagebrush, wildflowers, abundant lush grasses and vibrant colors in the spring (May/June)
• Passing through the small, accommodating, and friendly communities of Carey and Arco, Idaho (the only “civilization” and resupply towns on the route).

Riding Season

The timing of this route can be tricky, but it can also allow for an incredible experience. Spring time in Craters of the Moon Monument and Preserve from late April to Mid-June is the best time to ride the route. Early to late June is when water is most plentiful. The seasonality is greatly impacted by winter which determines when the snow is melted and the dirt is dry enough to ride. During this time, expect temperatures in the low 20s to mid-teens at night up to the mid-80s during the day. Daytime riding temperatures in early to mid-June are typically in the mid-50s to 70s when clouds are in the forecast.

From April to early May, snow could still be along much of the route, during a heavy snow year, but you may also be one of the first people out there that time of year. Water is scarce that early because wells are not yet being open for livestock and some creeks haven’t begun to flow. This is why June is the most optimal month to ride it. It also means all the wildflowers and grasses are in full bloom and it’s warm enough to start seeing reptiles moving along the trails.

It’s best to avoid the summer months. The heat and potential smoke from wildfires can make for an unpleasant ride, although there may be weather windows depending on the year. Fall is another opportune time to ride, typically from late September to Early November, although the route has yet to be ridden by anyone during these times, so more information is needed to understand what the experience may be like.

Seasonal hours at the Robert Limbert Visitor Center in the Craters of the Moon National Monument and limited water availability are two potential challenges when riding this route “too early” or “too late”.

Note: When heavy precipitation persists over several days, the road and trail surfaces will become very muddy and impassable. However, it all depends when and where those often isolated storms hit! You can take your chances, or play it safe.

Water

Water is scarce along this route. Much of the water quickly percolates through the porous lava rock and sand. Depending on your speed of travel, intended camp spots, and familiarity with the desert, the amount of water you carry will vary. 5 to 8 liters is recommended as a starting point. A filter or purification tablets, and a handkerchief as a pre-filter are recommended.

Definite water can be found at Silver Creek, and towns of Carey and Arco. If you’re in town, drink water, and always leave town at full capacity. Water sources on the route are nonexistent outside of an occasional well, stream, cattle tanks and a handful of “lakes”, which are difficult to locate and are seasonally dependent.

Water availability heavily depends on the time of year. If ridden too early or late (in April and May; October and November), wells and water spigots may not be open yet due to nighttime freezing temperatures. The Robert Limbert Visitor Center inside Craters of the Moon National Monument has seasonal hours and isn’t open 7 days with longer hours until Memorial Day.

Water may be cached along the route, although there are no defined places. Please ensure all containers are secured so they don’t blow away, and are retrieved after the ride. See more information in the Water Caching section under Logistics.

All known water is marked on the Ride with GPS route, although these are not 100% guaranteed to be available. All water sources should be treated.

Camping

This route features some really cool camping opportunities including inside an old volcano, on the rim of a crater, and even stashing the bike and hiking into the Craters of the Moon Wilderness with a free backcountry permit for the night!

A majority of this route takes place on public land within Craters of the Moon Preserve and Snake River Plains managed by the Bureau of Land Management (BLM) and is open to dispersed camping. However, there are very few existing campsites on this land – we should aim to keep it that way! (i.e. don’t build new fire ring pits, follow Leave No Trace principles, etc.)

Two developed campgrounds with amenities exist along the route. Silver Creek Campground (near mile 74) is a free, non-reservable site with designated tent pads and vault toilets. Sites can fill up quickly with car and RV campers, although with a little creativity, many other dispersed camping options are nearby. Lava Campground in the CRMO Monument is a paid option with 42 non-reservable, first come first serve sites with picnic tables, potable water, and vault toilets. In-town camping is also available in Arco on a private residence (slightly off route).

Ideal camping areas are marked on the route.

Services and Food Resupply

There are two towns along this route for food resupply. Riders need to plan for multiple days of food between these points.

Carey is the first town (around mile 83) with limited services and resupply. There is one convenience store with reliable hours. Itty Bitty Farms is an excellent stop for fresh produce! 93 Bar and Grill is the only restaurant in town. There are no hotels for lodging in Carey.

The Robert Limbert Visitor Center inside the Craters of the Moon National Monument is the second location with very limited services. When open, the visitor center has potable water, vending machines with snacks and drinks, and indoor restrooms. Even when the visitor center is closed there is an unlocked door on the east end of the building with an emergency phone. The room could be used for emergency shelter from bad weather, but not for sleeping in. There are also power outlets here.

Arco (around mile 217) is the third and final location for services and resupply along the route. There is a well-stocked market, a city park with water, restrooms, power outlets, and shelter, as well as several restaurant and lodging options. There is also a free, private campground right in town that is welcoming towards cyclists and has great reviews on Warmshowers.

When in doubt, it’s always a good idea to call ahead to make sure they’re open if you’re relying on these services.

Recommended Bike and Gear

The Great Rift Dirt Tour is largely a mountain bike route – it’s definitely not ideal for gravel bikes. Much of the terrain and drivetrain maintenance are reminiscent of routes with a lot of singletrack. Don’t let the lack of singletrack and minimal elevation gain convince you otherwise. A minimum of 2.2” tire is recommended. Fast rolling tires in the 2.3” to 3” range will be appreciated. Tubeless tires with an ample amount of sealant to combat thorns, cactus and sharp lava rock is advised. Fat bikes aren’t out of the question, but may feel like overkill at times. Front suspension may also be appreciated by those who want a smoother ride as much of the terrain is bumpy and rugged.

Brief History & Ecology

These are the traditional and ancestral lands serving as home and migration corridors for many people, including the Northern Shoshone, Western Shoshone, Bannock, Northern Paiute, and other indigenous peoples. Six species of large mammals are known to inhabit the area: mule deer, elk, pronghorn, moose, cougar, and black bear. Additionally, fox, wolves, coyotes, badgers, weasels, and many other native species continue to pass through and inhabit this landscape. While Idaho isn’t known for its reptiles, this region is home to 13 reptile species, including rattlesnakes, gopher snakes, longnose leopard lizards, and desert horned lizards, among several others.

Historically, this region was home to grizzly bears, bison and bighorn sheep. The last known grizzly was spotted and photographed by Robert Limbert during an expedition along the Great Rift in 1921.

• Paved: 14%
• Smooth Gravel: 13%
• Rough Gravel: 27%
• 4×4 Road: 46%
• Singletrack: 0%

Bikepacking is still relatively new to Carey, Arco and Craters of the Moon National Monument and Preserve, so it’s critical that all riders strictly follow LNT principles and be good stewards. Each rider is responsible for ensuring bikepackers have a positive reputation with other public land users, ranchers, and land managers.

Timing & Weather

As mentioned in the Riding Season section, the timing of when to ride this route is pertinent to the weather and the access to water. Spring season in this region ranges from April to early June. Spring rainstorms can be isolated to a narrow area or broad across the Snake River Plains. When the surface of these roads and trails gets saturated from several days of heavy precipitation, they are impassable and very muddy.

As referenced in the Water section, timing also matters when relying on wells to be full, spigots to be on and the Robert Limbert Visitor Center to be open longer and more frequently.

June is a wonderful, and likely the most ideal month to ride this route with the blooming wildflowers, lush grasses, and water availability. Best results come from planning the trip around the forecast – be prepared for changes in the weather.

Fall riding – information on the best time to ride during the fall is still being gathered. September can still be quite hot, and October–November may bring more precipitation and chilly temperatures. If you have ridden this route during these months, please reach out to Aaron Couch, the route developer, and share your knowledge and experiences with him.

Starting Points & Route Direction

The intended riding direction is clockwise to effectively optimize food and water resupplies. In this direction, the first town and resupply is Carey before heading back into the Craters of the Moon Preserve on the Interior Loop. The interior loop may be ridden in either direction – riding counterclockwise can be a strategic decision for those looking to cover more miles before camp, while still camping at the same intended location marked on the map (Snowdrift Crater).

Fees and Permits

Craters of the Moon National Monument is a fee area. The entrance gate lies just down the road from the Visitor Center near the Campground Entrance. To proceed along the road, all riders must pay the fee or have one of the accepted Interagency Passes.

From the Craters of the Moon National Monument website:

“Whenever the Loop Road is not fully open to automobile travel, no entrance fee is charged. Depending on weather, this occurs roughly from November through April. Check current conditions.”

Water Caching

Water may be cached almost anywhere along the route where it may be needed. A high-clearance and four-wheel drive is recommended to drive into the Craters of the Moon National Preserve and Great Rift Backcountry Area. Unless there is an additional person not riding in the party caching water for you, plan on an additional day to cache water along the route and an additional day to retrieve all water containers. The terrain is slow-going in vehicles, too. Refer to the BLM Travel Map under Additional Resources.

Below are some rules and ethics when caching water:

• • Hide it well to ensure it’s there when you need it
  • Mark with date, name & phone number
  • Secure all empty containers well

• PACK IT IN, PACK IT OUT

Desert Safety & Navigation

The high desert is both harsh and, with the right preparation, inviting. I certainly advise checking the forecast before the ride, but typically the weather is warm (70-80 degrees) and sunny during the day, with nighttime being cold (20-40 degrees). These nighttime temps keep the bugs at bay, and I strongly recommend sleeping under the stars.

Helpful Gear

The high desert will put extra stress on your bike and body. Sunscreen, chapstick, and a neck gaiter or handkerchief will be useful. A first aid kit you’re familiar with is a good idea too. And a helmet, of course.

It’s critical you have the skills and tools to repair flat tires! Please use tubeless tires if at all possible. Plugs, extra sealant, needle and thread, spare tube, patches, a pump, and CO2 are the minimum. Durable tires are advised.

The sand and any mud you encounter will be hard on your drivetrain, so be sure to have a rag, a brush, and some chain lube to keep it fresh. If the surface becomes too wet, it turns into gritty, sandy, peanut butter mud. Multiple days of this will make much of the double-track and dirt roads impassable.

Don’t underestimate the miles – the terrain can be slow and bumpy. Toss in a headwind in there and 30 miles can take you most of the day.

It is strongly advised that you carry multiple forms of navigation with you, and a satellite communication device, such as a Garmin InReach or SPOT, in case of emergency. Note that much of the Craters of the Moon Preserve and Great Rift Backcountry Area are very remote, with spotty cell service, and may be several hours away from the nearest main road or town (even by car).

Wildlife Safety & Food Storage

The route lies on a landscape home to many wild animals. Most of the wildlife poses no concern or threat to humans passing through their territory, providing that an ample amount of respect and space is given.

Rattlesnakes do inhabit this region. Be aware when walking through brush, stepping down from the bike, or while around camp. If you do see or hear a rattlesnake, do not disturb it. They will leave you alone if you leave them alone.

Many species of rodents inhabit this region as well and can easily ruin a trip if they get into your gear, bags, or food. However, they are not habituated to human presence in most of the backcountry Preserve like they are on many other public lands. Keep your gear and food near you at all times. Consider a rodent-proof bag, such as an Ursack, and scent-proof food storage bags.

Bears, although rare, and other predators also live here. While this landscape is home to black bears, traditional food storage methods commonly done in grizzly bear country and other areas where bears are habituated to human presence are not really necessary. The food storage methods mentioned previously for rodents and Leave No Trace Principles will suffice for not attracting bears to your camp.

Always respect all wildlife, never directly approach, and give them safe distances, and you will likely have positive encounters.

Highway Riding

There are several miles of highway. The route also crosses the oncoming traffic lane many times. Riders must understand and follow the Idaho Traffic Laws, ride defensively, wear bright colors, and use flashing front and rear lights.

The “side quests” along the highway are encouraged and recommended to break up the time on the highway and reduce potential vehicle interactions. Plus, they’re just fun!

• Great Rift Dirt Tour Community & Discussion Group
• Ride With GPS Route Guide
• Craters of the Moon National Monument and Preserve Travel Map (georeferenced for use with Avenza PDF)
• Aaron’s Instagram (@aaronrcouch) has more information on the route, including a saved interview with detailed reflections from a rider who completed the route in 2023.
• Follow @greatriftdirttour for future updates

Aaron Couch created and stewards this route. Here is a little about Aaron in his own words:

I have 5+ years of route developing experience, mostly for customers of a bike shop, specifically for events like the Fitz-Barn, Around the Rock, Togwotee Winter Classic, Wydaho One Hundred, etc. I have worked with Kurt to help develop some routes Bikepacking Roots has already used, including the Maah Daah Hey and Intermountain Connectors from the WWR to GDMR. I’ve recently begun sharing more routes openly and publicly as a Ride With GPS Area Ambassador. These routes include Wydaho One Hundred, North Valley Agriramble, and the Great Rift Dirt Tour.

I live within 2 hours of the start of the Great Rift route. I developed it through intensive research and 5 days of scouting in June 2022. I will continue to steward and update the route as needed in the future.

Be sure to check out Aaron’s website Destination Reroute to read more about his bikepacking adventures and route creation.

Aaron has offered to be available to answer questions if you are planning a trip on this route. We encourage you to be respectful of Route Stewards time though and to review publicly available materials first before reaching out with questions.

Please also get in touch with any updates on route conditions that may be relevant to other riders.

Please submit your questions and comments on the route using the contract form below.

This route traverses the traditional lands of the Shoshone, Bannock, Cayuse, Umatilla, and Walla Walla.