9 Thrilling Drives Across America

En español | Parts of Saddle Road (Route 200) across the Big Island are steep, narrow and rough enough. But 15-mile Mauna Kea Summit Road, branching north to the dormant volcano's peak, climbs through switchbacks, lava chunks and dense fog to a group of international observatories at 13,780 feet.

Officially called State Route 11, the only U.S. road crossing the Arctic Circle consists of 400 potholed miles across tundra, with no travel services — so come prepared. View the spectacular wildlife from your car to avoid scaring (or otherwise annoying) the wolves, bears and other animals.

Never lacking in bluff-hugging hairpin turns, the iconic Highway 1 (the Pacific Coast Highway) is at its most dramatic through the 90-mile stretch known as Big Sur. Between San Simeon and Carmel, the famous road passes gorgeous beaches, scales sharp cliffs and crosses 33 bridges hundreds of feet above the shore.

Driving this one-lane, 101-mile U.S. Forest Service road takes six to eight hours at a maximum of 15 mph — a memorable crawl through 3 million acres of pristine wilderness and beautiful mountain views. If you meet another car going the opposite direction, be prepared to back up a long way to find the rare wider spots between the mountain wall and the 1,000-foot drop at the edge.

This graded-dirt stretch of State Route 261 is a gauntlet of abrupt switchbacks carved into the face of Cedar Mesa's scrub-covered red rock, with some stunning scenic overlooks. The 1,100-foot descent is the longest three miles you'll ever drive, especially if you peer over the sheer edge at remnants of cars that unexpectedly parted ways with the road.

U.S. 550's steep 25 miles between Ouray and Silverton take in some of the Rockies' wildest peaks. If blind S curves and scaling repeated mountain passes at over 10,500 feet without benefit of a guardrail induce panic, make the trip from north to south, so you'll be in the inner lane.

The most scenic and nerve-wracking stretch of the state highway tracing the Rio Grande winds up and down arid mountainsides and twists through slot canyons for 40 miles amid Big Bend Ranch State Park. Wild animals and rubble can make steep grades and blind rises even more difficult to navigate.

Yes, it's part of Interstate 10, but the 18.2-mile bridge across the country's largest swamp is downright eerie. Perched on columns, the narrow roadway is bumpy enough to shake your fillings loose, and moss-shrouded bald cypresses poking from the water inspire visions of swamp creatures rising from the muck.

It's low gear all the way on this narrow, rutted 7.6-mile climb up the Northeast's highest peak for a stirring view encompassing five states and Canada. There's nothing between you and the precipitous drop-off, and there's scant room for passing. The trip down is milder — if your brakes are in good repair!

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