A pride of the state, this working museum crafts pottery mosaics in the style of Pennsylvania's earliest European settlers.

Alleyway plaque commemorating the death of a fictional character in The Maltese Falcon, not far from the author's home.

The only surviving leech house in the United Kingdom was a home for bloodsucking worms until the 1900s.

This giant geoglyph of mysterious origins is now the site of neo-pagan rituals.

Preserved baths in a Victorian-era spa town frequented by the most famous people of its day.

A whimsical village of unique treehouses resides in a Washington forest.

A magical museum of fairy tale treasures near Cyprus' buffer zone.

This massive chalk hill carving is one of England's most beloved giant horse geoglyphs.

What was once thought to be a wellspring of unicorn bones is actually just a prehistoric burial site.

Remote ruins of a 2,400-year-old Iberian settlement.

The grounds of this Jacobean estate contain one of the oldest mulberry trees in England.

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

The world's largest prehistoric copper mine had 30,000 animal bones scattered throughout the maze of passageways.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

Europe's largest natural bridge has a 19th century royal chateau built into its side.

A visionary Italian architect created an impressive cluster of concrete structures for a family's private tomb.

Mirrored floors and arched shelves create the illusion of an infinite tunnel of books.

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

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

Commonly referred to as the most photographed Victorian home in the United States.

Romans built the world's tallest artificial waterfall in 271 BC.

At just 25 inches at its narrowest point, it's one of the tightest streets in the world.

An important pilgrimage site for pagans and early Christians, named for a Celtic goddess-turned-saint.

A modernist landscape of water and sci-fi concrete.