Front Royal to Rockfish Gap, Virginia
Distance: 105 miles
Curve Rating: Moderately curved—like a leisurely Sunday drive
Built between 1931 and 1939, with sections of the route constructed as part of the New Deal relief effort, this sweeping road through Shenandoah National Park crests the Blue Ridge Mountains (hard to believe that noisy Washington, D.C., is just 75 miles away). You'll see oak trees and evergreens on your leisurely trip, in addition to white-tailed deer and wild turkeys. Just make sure to stop at Range View Overlook (at mile 17.1) for a first-rate view of the fog-veiled mountains.
Mile-Marker Moment: Big Meadows, at mile 51, boasts 130 acres of wildflowers in spring, summer, and fall. You'll also see doe and their tiny fawns during the warmer months (540-999-3500).
Newfound Gap Road
Pigeon Forge, Tennessee, to Cherokee, North Carolina
Distance: 40 miles
Curve Rating: Moderately curved—like a leisurely Sunday drive.
It's the only route that completely crosses Great Smoky Mountains National Park, rising out of Pigeon Forge (yes, the home of Dollywood) before climbing 3,000 feet and descending across the state line. You'll pass through hardwood and evergreen forests and get a glimpse of Clingman's Dome, the highest point in Tennessee.
Mile-Marker Moment: You won't see an actual sign, but keep an eye on your odometer and stop at mile 21.5—this is Newfound Gap (5,048 feet), where FDR dedicated the park. Even better: You can stand in two states at once (865-436-1200).
California Highway 1
Carmel to San Simeon
Distance: 90 miles
Curve Rating: Curved—don't even think about speeding
With the Pacific Ocean on one side and jagged cliffs on the other, this two-lane road features gnarly curves above the pounding surf. But your rugged trip through Big Sur territory brings rewards—you'll pass spouting whales and an 80-foot waterfall that drops into the ocean at Julia Pfeiffer Burns State Park. Near drive's end, stop at the Hearst Castle museum; once the opulent home of William Randolph Hearst, the site is as glittering now as it was then (watch for wandering zebras from the estate's one-time private zoo).
Mile-Marker Moment: Look for Piedras Blancas Elephant Seal Rookery, with vista points from mile 61.3 to 65.1, where you can glimpse more than 16,000 of the water-loving creatures (831-667-2100).
West Glacier to St. Mary, Montana
Distance: 50 miles
Curve Rating: Very curved—pack the Dramamine
This two-lane route hugs the mountains of Glacier National Park—the road is so narrow and curvy that large RVs are banned—but it's the most jaw-dropping way to cross the Continental Divide, as towering cedars give way to thundering waterfalls and alpine meadows. With the road literally carved out of the side of the mountain, shoulder lanes are sometimes missing along the way, and rock walls are all that separate you from the gaping area below at some points. If you're even remotely afraid of heights, drive on the road from east to west—so you can cruise in the inside lane next to the mountains.
Mile-Marker Moment: Garden Wall Overlook, at marker 31.5, bypasses the crowded Logan Pass summit (by a half-mile) and offers a great place to look at grazing mountain goats and your just-conquered route (406-888-7800).