The remains of an ancient Roman city are hidden underneath Bologna's beautiful public library.

A striking memorial recalls thousands of Bolognese men and women killed fighting fascists in World War II.

Legend has it this fountain built to symbolize the Pope’s power hides a strange secret concerning Neptune's manliness.

Over 100 towers were built in Bologna during the Middle Ages, but only 22 survive.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

Known simply as "The Hand," this famous public sculpture in Berlin was featured in a Depeche Mode music video.

One of the oldest cemeteries in Germany was originally used for victims of a cholera epidemic.

You've probably seen these distinctive orange-tiled columns on the big screen.

Dine at a legendary after-hours joint frequented by David Bowie and Iggy Pop.

One of downtown Berlin's last reminders of its Communist past.

Inside this Jewish cemetery is a memorial to soldiers who deserted the German army and were executed.

Once a path for Jewish funeral processions, this unassuming alleyway is rich in local lore.

This water-tower-turned-high-end-apartment building was once the site of an early Nazi concentration camp.

Dedicated to the European Sinti and Roma peoples murdered during the Holocaust.

Visitors are treated to a stained glass kaleidoscope interior inside this work of art.

Nordic giants resurrected from the sea and restored to their former greatness.

A spiralling hourglass-shaped tower rises from the forests in Denmark.

Dozens of musicians have planted trees in this Danish park, and donated songs to go with them.

A Danish fisherman spent 25 years covering nearly every inch of his home with tens of thousands of shells as a gift to his wife.

One of Jeff Koons’s largest sculptures and his first commemorative work.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The video game-themed street art first popped up in the French city.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.