Millau Bridge, Tarn Valley, France

High Notes: Never particularly keen on forming a line, the French decided in the late 1980s that something had to be done about the holiday gridlock on the A75, the main route linking Paris to the south of France. In 2004, they revealed the fruits of their impatience: the highest vehicular bridge in the world and, some would say, the most beautiful, thanks to architect Norman Foster. Suspended from seven enormous piers, the Millau Viaduct soars above the Tarn Valley at a maximum height of 1,125 feet—63 feet taller than the Eiffel Tower—and is 1.5 miles long. With the right combination of cloud cover and the local red wine, the support cables of the bridge almost look like the rig of a sailing ship on a phantom sea of mist. Given that it was built to make the life of tourists a bit speedier, it's a little ironic that the Millau Viaduct has become a tourist attraction itself. It costs about $9 to cross the bridge in a car during July and August (a bit less in winter). If you're feeling all Lance Armstrong and intend to cycle across, then go from south to north so you'll benefit from the three-percent slope that runs in that direction. Just don't look down.

Where to Catch Your Breath: The charming Château D'Ayres, which dates to the seventh century, is 25 miles from the bridge and a great base for exploring the Tarn Valley and the cliffs and gorges of France's Massif Central.

Doubles at Château D'Ayres from $140

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