Alternate routes enhance adventuring along the Great Divide Route in Montana

CENTENNIAL VALLEY, Montana -- America's Great Divide Mountain Bike Route is a series of rural backroads from Banff, Alberta, Canada to Antelope Wells, New Mexico that together form a premier route for adventurous bicyclists and, increasingly, motorcyclists.

Following a network of primarily unpaved backways, it traverses some of the most rural regions of the Rocky Mountain West.

At its northern end, it parallels the Continental Divide -- and the Continental Divide Trail for hikers -- as it winds through western Montana, not far from my home in Idaho.

Judging by the number of ride reports by adventure motorcyclists -- ADV riders, they are called -- it seems that more and more backroad travelers are taking the route each year. As an ADV rider and backcountry driver myself, I became curious about the route in the summer of 2009, and decided to have a look.

Crossing the Continental Divide via Montana, Idaho's Centennial Mountains

Red Rock Pass Road

CENTENNIAL VALLEY, Montana -- I long wondered whether there is a route across the Centennial Mountains, a unique east-west-trending Continental Divide range that rises more than 3,000 feet above the valleys that flank it along the Idaho-Montana border.

My goal has been to cross from the Idaho side to connect with Montana's scenic Red Rock Pass Road (in the photo), in Centennial Valley. The valley is the locale of the beautiful Red Rock Lakes National Wildlife Refuge.

Historic Bannack, Medicine Lodge roads alluring links between Idaho and Montana

Bannack Pass

One of the backcountry routes I enjoy the most is the 19th-century road over Bannack Pass, in the Beaverhead Mountains along the Continental Divide between eastern Idaho and southwestern Montana.

More than a century ago, the old Bannack road linked Montana's territorial capital, today's ghost town at Bannack State Park, with Corinne, Utah, not far from the Transcontinental Railroad.

Stagecoach station

Today, it is a little-traveled single-lane dirt road that combines homestead-era log structures, inspiring northern Rocky Mountain scenery, a gear-soaking stream ford and easy access to a day-long loop.