A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

The famous abolitionist’s preserved estate is one of Washington's finest monuments to its great Black citizens.

The walls of the iconic dome are hollow and have a secret stairway.

A nostalgic bibliographic gem.

There’s a hidden military meme engraved on the World War II Memorial.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

The ancient heart of Tunis is an enormous maze of narrow streets and alleyways.

An ancient Phoenician citadel once stood at the site where Queen Dido first landed, according to legend.

This museum in the famously blue neighborhood of Sidi Bou Saïd showcases a traditional Tunisian lifestyle.

Filled with history, this cemetery is maintained each summer by a few hungry goats.

A small world of mechanical magic and metal merry-go-rounds in a Outsider art Museum.

Every summer, this shrine sets up a tiny drinking fountain reserved for thirsty apians.

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.

More than 8,000 drinking jugs say “Cheers!” to a guy named Toby.

An antiquated German apothecary on Chicago's North Side.

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

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

The world's oldest rose is so tough it survived being bombed in World War II.

These ancient sunken lanes were naturally tunneled into the soft ground by countless footsteps.

A treasure hunter's tiny bar, harboring celebrities since 1959.

Beautiful carved tunnels.