Erotic art covers the walls of the largest ancient pleasure palace.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

Jesus' footprints and the first catacombs in the world.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

A brush maker used his factory to protect blind Jews from the Gestapo.

Cold war icon and onetime "hole" in the iron curtain.

A restaurant and observation deck built in a unique broadcasting antenna.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

A fascinating insight into daily life in the Eastern Bloc.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

A little sculpture with a large wardrobe.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Climb inside an iron crystal magnified 165 billion times its normal size.

A pair of trees near a Hong Kong shrine are said to grant wishes, but only the ones they hold on to.

Climb to the top of the world's largest seated bronze Buddha.

The celebrated eyesore created by starry-eyed sweethearts.

A unique military outpost carved into a rocky outcrop in the English Channel.

A quaint medieval harbour where Benjamin Franklin landed in 1776.

This facility has manufactured stunning tapestries for France's royalty ever since the 17th century.

The vibrant buildings in the “capital of the comic strip” celebrate the art form that made it famous.