U.S. Route 2 is not a road for all seasons. Winters can be brutal in North Dakota and Montana and springs arrive late. But in warm weather the prairie countryside comes alive, with fields of mustard and clover providing wide swatches of color.

This is a long-distance drive, stretching 900 miles through the nation's northern tier. Farmland surrounds much of the route. There are thousands of pothole or kettle lakes; these round depressions were left by retreating glaciers and are now colonized by duck families. The sky is immense and solitude marks most of the trip.

The fracking boom, which has turned North Dakota into the second-biggest petroleum-producing state, has transformed some parts of the journey and introduced a lot more traffic. But Route 2 still goes mostly through very rural areas, according to Kim Schmidt, a spokeswoman for the North Dakota Tourism Division.

The road starts out flat in the east and goes through rolling farmland before hitting the Badlands out west, she said.

Once travelers cross the Montana border, there's still nearly 500 miles before Route 2 becomes Going to the Sun Road, which splits Glacier National Park in two. The road skirts waterfalls, avalanche chutes and alpine formations carved by millenniums of ice. With its switchbacks, narrow lanes and steep drops, the drive is not for the faint of heart.