An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

Old Danish castle immortalized in Shakespeare's Hamlet.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Copenhagen's celebrated theme park and gardens.

One of Mexico's least-visited archaeological sites is tucked away inside a theme park.

A graceful natural rock formation stands astride the point where the Gulf of California meets the Pacific Ocean.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

These ruins of a pre-Columbian cliff village are among the most beautiful and well preserved in New Mexico.

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Thomas Jefferson's estate is home to hundreds of varieties of historic fruits and vegetables.

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

The graveyard holding the remains of George Washington's slaves was forgotten for nearly 200 years.

A museum dedicated exclusively to aircraft used in the military.

The only place for a truly presidential dram.

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

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

This historic train station has been converted to a locomotive themed hotel.

All you ever needed or wanted to know about America's favorite whiskey, but not a drop to drink.

An enormous, inside-out glass globe built in 1935.

An incredible airplane graveyard sits outside this small museum dedicated to preserving aviation history.

A motel dedicated to Southwestern nostalgia.

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