If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

The world’s largest truck stop includes a barber shop, chiropractor, and a huge museum with antique trucks.

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The world's longest known cave system.

Eight rare Corvettes are swallowed up by a sinkhole in Kentucky's National Corvette Museum.

This Niagara Falls tourist trap is a world bright with neon and curiosities that will inspire love, hate, or a mixture of both.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

One of the largest underground systems runs under Canada's largest urban center.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

A second generation sun-powered marvel lights up the night.

An historic and oft-filmed spot for musclebound iron pumpers on the Pacific coast.

The park is home to the United States's only still-operating Dutch windmill.

This is the last hand-cranked chain ferry of its kind in operation in the United States.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The first declared National Monument in the United States.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

The giant squid's 27-foot-long corpse lies preserved within a Sarasota aquarium.

A building so large that it has its own weather.

An idyllic swimming pool tells the tale of Hemingway's trouble with women.