An alchemist's "magic door" stands in the middle of a Roman park.

A submerged archeological park still holds the wonders of a Roman Sodom.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

A collection of outdoor mystical statues paying homage to indigenous Australians and ecological stewardship.

Once the path of a railway tunnel, now home to thousands of glowing insects.

An Australian lake whose pink hue defies scientific explanation.

Australian Lake set aglow by Noctiluca Scintillans.

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

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Eighty million natural history specimens call this gargantuan museum home.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

Banksy gives themself artistic license with this piece of London street art.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

A unique collection of Swiss art brut and naïve art displayed in an old warehouse.

Constructed along the shores of Lake Zurich, this pavilion is a walk-through work of art.

The world's longest and deepest train tunnel.

Lucerne's central prison was converted into a tourist hotel with a bare minimum of changes.

One of the highest emergency huts in the world has been waiting almost a century to give imperiled climbers a place to lie down.

The excellent Swiss museum of witchcraft is led by a modern witch.

A tower-like theater in the Swiss Alps built to withstand the high winds and avalanches of the mountain pass.

The Swiss artist's bulbous and overgrown shape-shifting sculpture controversially graces the center of Bern.

One of a series of no-purpose kinetic artworks by Swiss sculptor Jean Tinguely.

A 22-million-year-old sandstone cave is a natural habitat for award-winning cheese.

This small museum displays a collection of outsider art and scale models of past "treatments" for mental illness.