A forgotten "city of water" underneath the famous Trevi district.

Wandering this ancient burial place offers a glimpse of the afterlife in the fresco-adorned tombs of an ancient Etruscan civilization.

The pioneer of psychoanalysis spent the final year of his life here, still seeing patients on that famous couch.

Following the trail of an old metro line, this scenic path is haunted by a creepy spriggan statue.

An artistic tribute to the famous singer, just around the corner from where he was born.

The television series' iconic giant foot was borrowed from this classical painting.

A historic London cemetery now serves as a nature park incorporating gravestones & memorial statues.

Hear the quietest sound from across the dome.

The site of London's first coffee house has been serving refreshments of one kind or another for 360 years.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Eighty million natural history specimens call this gargantuan museum home.

Winding paths and ramshackle mausoleums in the oldest "park cemetery" in London.

A kaleidoscopic warehouse-maze of handmade neon signs.

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

This permanent collection of preserved bodies taken from Irish bogs is one of the leading authorities on such morbid mummies.

A modern sliver of architecture in Roma.

Medieval town turned hippie commune, once home to the secret foreskin of Jesus Christ.

Geothermal waterfalls in Tuscany.

This immaculate and historic water garden culminates in a massive stone dining table with an inset fountain for chilling the wine of the Cardinal's guests.

This 16th-century monastery has been turned into a surrealist architecture compound.