The perfectly preserved underground rooms where Churchill plotted the war against Germany.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

The last bastion of Roman presence north of the Alps looms over a German town.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

Museum celebrating the ocean, with the largest wunderkammer dedicated to sea exploration.

Fountain where visitors can earn a license to be mad.

What appears to be an ancient Roman temple is actually a Catholic church.

A mushroom-shaped outcropping that has come to be the symbol for an entire town.

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

Mysterious tombstones thought to be remnants of Atlantis.

Windblown rock formations in an ancient Roman quarry.

This cliff-face port is considered a masterpiece of mining engineering.

This one-of-a-kind archeological site is home to strange prehistoric ruins, the original use of which is still a mystery.

This ancient market is often referred to as the oldest shopping mall in the world.

Ancient ruins hidden underneath a modern luxury hotel.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

The studio built by fascists in the hopes of "reviving the film industry" with the occasional propaganda film opportunity thrown in.

The Pope’s secret escape route.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

The roof of this ancient mausoleum is made from a single Istrian stone weighing a massive 230 tons.

A medieval, mosaic-lined baptistry built by a heretical Christian sect.

An incredible mosaic-lined monument said to have held the remains of an ancient Roman empress.

Psychoanalyst Carl Jung reported a paranormal experience after visiting this mosaic-lined Roman baptistry.