Four-story concrete hotel never opened to customers.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.

This museum in a Paris apartment gives a unique look at the iconic French singer's life.

Original cabaret handbills, posters, and feline artwork are a purrfect highlight of the Museum of Montmartre.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

This controversial Irish show cave is home to a massive formation known as the Great Stalactite.

A house of courtship where the Jazz Age's most storied lovers got their start.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

The restaurant keeps a hidden séance room on the second floor and reserves a table for the spirit of the former owner each night.

Shop for books in the New Orleans house where William Faulkner once lived.

Even in death, he's still your huckleberry.

One of the last socialist halls still standing in the United States.

The famed architect designed this Minnesota gas station of the future with a lookout tower.

Beating out all other concrete competitors, this massive garden feature's pointy hat has earned it a world record.

Underneath downtown Lincoln resides a network of caves that was also the city's first brewery.

A fascinating collection of art made from petrified wood and fossils by two octogenarian twin brothers.

The deserted railroad town had a last gasp as a ghost town attraction before being abandoned for good.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

Hidden behind Lincoln's head is a 70-foot-long chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.

The highest point in South Dakota contains the ashes of Valentine McGillycuudy, the "Holy White Man."

A cemetery housing wild west legends in South Dakota.

Native Americans built this circle of stones, which was used to predict astronomical events.

An unusual geological feature towers over the remains of a dark episode in United States history.

This legendary "evil" doll has been haunting the citizens of Key West for over 100 years.