A museum dedicated to one of Paris’s most famous residents, tucked into a corner of one of the city’s most famous squares.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

A memorial dedicated to a highly decorated Marine and Korean War veteran, who also happened to be a horse.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

These unusual rooms on wheels are holdovers from the 1960s.

The menacing creature had a tremendous influence on the local culture before being exposed as a hoax.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

Edgar Allan Poe's old dorm is now a shrine to the author's legacy.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

Massive puppet-automaton machines created by French artist collective Machines de l’Ile.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Home to the "Rat King" of Nantes and other wonders of the natural world.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

This 29-ton granite ball spins around at the slightest touch thanks to a scientific phenomenon.

A small Richmond island dotted with the remnants of hundreds of years of history.

The watery grave of an impractical idea.

This rare vessel mixed luxury with labor before being converted to a museum and sometimes haunted maze.

This posh mansion began as a family's estate and ended as the site of a murder ripped from the pages of a pulp novel.

A former major munitions plant that has been converted into a sprawling art space.

The narrowest house in America is seven feet of pure spite.

This stately building in Alexandria, Virginia was built by Freemasons to honor one of their most famous members.

Eighteen miniature death-scene dioramas.