In a 345-million-year-old cave that's 200 feet underground, dinner awaits.

The largest of London's subterranean rivers and once a mad, bad center of London life.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

These spectacular ruins were built by Spanish padres in the 17th century.

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

Wonderland replication in progress by one persistent man.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

"There's nothing there," and other lies the KGB told us.

The hidden lair of an alchemist rediscovered in a 2002 flood.

Countless grotesque faces stare out from this eerie Prague art wall.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

One of the oldest colonial buildings still standing in South America.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

An epic sculpture depicting a wagon and straining oxen.

From sax to spuds, get 'em all at this landmark music establishment.

A "Titanic" superfan changed his name to Jack and set up this strange shrine to the blockbuster, complete with Korean food and Tarot readings.

These two monoliths have stood at the entrance to the neighborhood since the days it was called "Hollywoodland."

A few iconic structures are all that remain of America’s first outdoor shopping mall.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

Contemporary art inspired by natural history and science drawing on ancient techniques in a modern world.

Crypt mausoleum in cathedral's basement contains relics of third century Roman martyr, Saint Vibiana.