A monument celebrating the idea of reaching inaccessible places.

The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.

The romance of early commercial flight still fills this Art Deco destination.

At 207 feet, one of the world's longest continuous escalators.

Walk the whole Mississippi River!

The secret city built by the Manhattan Project.

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.

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.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

There aren't too many operational funiculars around, but Pittsburgh has two!

This eerily well-preserved coal town was saved from destruction by a Sean Connery movie.

This erect, phallic geological spire wasn't always named so domestically.

At one time this small mining village was the highest town in America but now it sits abandoned while the mine churns on.

Air Force Academy Chapel made of 100 identical tetrahedrons works to inspire those of all religions.

Even in death, he's still your huckleberry.

The highest bridge in America was built for an almost unnervingly small amount of money.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

Experience a charming 1930's version of "infotainment."

See massive fossils that are over 200 million years old in northeastern Arizona.

A motel dedicated to Southwestern nostalgia.