Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

The fountain marks the area where hundreds of accused witches were burned at the stake.

Tiny effigies of the victims of Edinburgh's famous Anatomy Murders.

360° views of the city plus five floors of optical illusions and hands-on science.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

An eclectic art form practiced by untrained masters is celebrated at this museum in the heart of Zagreb's old Upper Town.

A self-proclaimed libertarian micro-state on a tiny bit of disputed territory between Serbia and Croatia.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

The remains of a sunken military ship wreck visible through clear water.

Humble beginnings for one of the world's most famous scientists.

A wonderfully strange collection of 500+ stuffed frogs doing people things.

Where the lovelorn find a home for their sentimental keepsakes.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

As can be expected from a centuries old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

Venice's "Island of the Mad."

A stunning 18th century pharmacy and medieval chemist's collection.

This Romanian village may have been drowned, but it is long from forgotten.

No one knows who built this strange cave of worship or exactly why.

A small town Romanian cemetery filled with darkly humorous gravestones.

The Jesus tree of Malta bears a striking resemblance to Christ on the cross.

This subterranean necropolis holds three floors of antler-dug grave caves.