From his Audi RS 6 supersedan, Stephan Wilkinson surveys canyons, caravans, and an infamous cannibal

Charging uphill is no problem for Audi's 450-horsepower, twin-turbo, 164-mph RS 6 supersedan, so I took it to Colorado's Rocky Mountains for a top-speed taste of three resort towns as different as a mint julep, a single malt, and a schooner of Stella: Colorado Springs, with its classic Broadmoor hotel; chic Aspen; and trendy Telluride. It's hard to imagine another state—or country—within which easy 250-mile-a-day back-road legs can provide such diverse and spectacular drives. Certainly the Rockies are the state's crown jewels, but Colorado is not all mountains. On the flats, the roads are a motorhead's mecca, most of them as smooth as an infant's buns and some so sinuous that they deserve to be on any location scout's list for car commercials.

Day 1: Colorado Springs to Aspen via Pikes Peak, 236 miles
One of my heroes is a shy, lanky German race-car driver named Walter Rohrl, who has given me more than a few rides in fast cars (most recently, a 206-mph scurry in the new $440,000 Porsche supercar, the Carrera GT). In 1987, Rohrl drove an Audi in the Pikes Peak International Hill Climb—after the Indy 500, the second-oldest motor race in the world—to become the first person to do the course in less than 11 minutes.

It was Audi's sixth straight Pikes Peak victory. What caught the car world's attention was that all those wins had been accomplished by cars that looked much like stock Audis running against everything from single-seat track cars to pure sports-racers. This set of trophies gave Audi great publicity, which it sorely needed after a controversial 60 Minutes report in 1986 disastrously faulted the Audi 5000 for "unintended or sudden acceleration" (it seems that drivers were pressing the gas thinking their foot was on the brake). Audi's racing wins helped revive the brand's popularity in the U.S. market after a near-death experience.

Today, climbing Pikes Peak, I would be Walter Rohrl racing up one of the world's highest drivable highways, a private toll road to the summit. At more than 14,000 feet, it is topped only by India's Khardung La Pass (18,380 feet) and three Andean passes on Chile's borders, all in the mid-15,000s.

That conceit lasted about three miles, on the curvy, nicely paved initial section. Ultimately, the pavement stops just short of the ten-miles-to-the-top marker, about two miles into the once-a-year racecourse, and from there on, the road is a dizzying, steep, frankly terrifying series of turns that range from high-speed sweepers to hairpins, all of them washboard dirt and gravel. There are no guardrails. None. Slide off any of the corners and first you'll make like a Cessna for a few moments and then tumble thousands of feet. Finally, at the naked, rubble-strewn, 14,110-foot summit are America's Sherpas: the people who work at—why am I not surprised?—the gift shop, which sells everything from Pikes Peak tchotchkes to drafts of oxygen.