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 longest water bridges in the world was built over a supposedly haunted swamp in Louisiana.

After a water tower painting was accused of being an ad, a simple fix was made that gave the city a motto.

The world's longest known cave system.

You thought Santa Claus didn't exist, but it turns out you were wrong.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

The palatial McDonald's that inspired Wesley Willis.

A display of magnificent stained glass windows is the first exhibit of its kind.

This historic hotel invented the chocolate brownie.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

Race through the maze, get your name on the sign.

This museum holds a fully-functional replica of the "Turtle," the first American submarine ever built.

House used in the 1971 horror film "Let's Scare Jessica to Death."

Holding multiple historical boats and an entire 19th century village, this New England attraction is the largest maritime museum in the world.

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.

A Looff creation in Santa Monica best described as “a California-Byzantine-Moorish-style fantasy.”

"The only replacement for a DC-3 is another DC-3."

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

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

A geological mystery on Camelback Mountain.

This immigrant bridge once spanned the Thames but is now a fixture of an Arizona city.

On the outskirts of a reborn ghost town, a decaying post office remembers the bad old days.