Mammoth Gravel Loop
105 Mi.(169 KM)
% Rideable (time)
Bill is a born and raised midwesterner currently riding in Minneapolis. He enjoys getting out of the city and exploring Minnesota, Wisconsin and Michigan by two wheels and finding all the best pizza the great north has to offer. A creative by trade, his camera’s always by his side ready to capture the best (and worst) parts of his adventures. Follow Bill on instagram at @seebillride
The Mammoth Gravel Loop is a bikepacking overnighter that traverses the St. Croix River Valley along the river of the same name. The route goes through Fish Lake and Crex Meadows State Wildlife Area’s before joining up with the Gandy Dancer Trail, one of Wisconsin’s many rail trails. The terrain throws a little bit of everything at you. From paved roads and rail trails to smooth and chunky gravel and a few short sections of sand. The sand sections are the only spots that gave me trouble on 700×40 tires. Everyone that had a wider tire setup rode through without problems. The sand sections are short and can quickly be walked if needed.
While we started in Milltown, WI the route has plenty of versatility and could be stretched into a two night trip if you wanted to shorten your mileage. Many of the cities along the Gandy Dancer portion of the route make great start/end points depending on how you want to split up your days. Rustic camping is available in various places along the St. Croix River. These sites are available on a first come first serve basis and fill up quickly during summer weekends. Otherwise The St. Croix River Campground and the James Mc Nally Campground in downtown Grantsburg offer reservations. If you don’t mind pitching your tent next to RVs and fifth wheel campers for the night, Brickfield Brewing is a stones throw from James McNally Campground.
Route Development: The original Mammoth Gravel Classic route and event were created by Frank Lundeen who operated the now closed CycloviaXC bike shop in St. Croix Falls. The event was created in the spirit of the grass roots gravel scene pioneered by Almanzo. The 2015 route that inspired the above was found on the Wisconsin Bike Fed website. Big thanks goes out to everyone involved in planning and scouting the route before me.
- If available, Sandrock Cliff Campground offers a great spot elevated above the St. Croix River.
- The Wolf Creek Bar and Grill is a great place to grab a quick beer or bite.
- The section of the route along the Gandy Dancer allows you to check out the fun small town Wisconsin atmosphere. Festivals and city events are plentiful during the summer months. Be sure to check out the cities websites when planning your trip.
- Take a break and grab a pint or a growler to go at Brickfield Brewing, Grantsburg’s craft brewery. From Kolschs to IPAs they are sure to have something to quench your thirst on tap.
- If your riding the route during the fall season check out Baker Orchard (bakerorchard.com) in Centuria for fresh apples and they even host a cyclocross race in October.
- Stop by The Crex Meadows Visitor Center to learn about the areas history and get some insights about what kind of animals to keep an eye out for in the area. Crex Meadows is a state-owned 30000-acre complex of marsh woodlands and prairies north of Grantsburg. Crex Meadows features colonies of nesting herons breeding eagles and osprey sharp-tailed grouse and trumpeter swans Karner blue butterflies and Blanding’s turtles as well as large concentrations of sandhill cranes waterfowl and eagles in the fall.
- Take a step back in time at the Soo Line Depot Museum in Frederic. Right off the Gandy Dancer Trail, you can’t miss the restored train car. The museum also has exhibits of old-time kitchen paraphernalia, school memories, old general store, farm implements and railroad artifacts.
- The best months to ride are between late May and mid October. The timing on the front and back ends is dependent on weather during the season but any time in between should provide great riding conditions.
- Prepare for the usual midwest bugs. Mosquitos and black flies are going to be the most annoying and most prevalent during the warmer months. A small bottle of bug spray is recommended especially if riding in the summer months.
- The weather in May and October can be variable with potential for spring rains or early fall snow and close to freezing temps. Between June and August you can generally expect perfect riding weather.
- Contact the city where you intend to start/finish to give notice of overnight parking and find the best place to leave vehicle(s).
- Black bears are in the area so it’s recommended to hang your food at the rustic sites.
- The Gandy Dancer trail requires a WI State Trail Pass for bicyclists 16 years of age or older.
- The route goes through or passes nearby plenty of cities with a handful of options for restaurants or convenience stores.
- Many lakes, rivers and creeks to filter water along the route if needed.
The route offers plenty of ways to customize it to your liking. We decided to start in Milltown, Wisconsin to split up the days equally. We had hoped to camp at Sandrock Cliffs which has about 4-5 rustic sites but due to an unseasonably warm weekend in October they were occupied by the time we arrived. We ended up staying at James Mc Nally Campground in downtown Grantsburg which was better than we had expected. Our site was right next to the river with a bit of a waterfall that was nice to fall asleep to. This also gave us the opportunity to checkout Brickfield Brewing for dinner and a few craft brews. If breweries aren’t your thing, Granstburg offers plenty of other options if you decide not to pack your meals. Check the hours ahead of time though.