This small chapel built into rock is the oldest place of worship in Luxembourg.

The official motto of Luxembourg reminds passersby of the Luxembourgish commitment to their national identity and sovereignty.

Dine amidst exotic plants at this former royal greenhouse.

The townhouse where the "Blood Countess" Elizabeth Báthory started her murderous career.

The beautiful baroque library of the Hapsburg empire.

Bits of architecture from a town destroyed in World War I now decorate this hotel garden.

A humble homage to a gravedigger tucked within the dignified English cathedral.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

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

In the early Roman Empire, people deemed traitors and criminals were tossed to their deaths from this rock.

This small church was constructed over the ruins of three temples dating to the Roman Republic.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

A rare example of a medieval house in Rome adorned with a melancholic inscription.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

This curious, round temple is the oldest still-standing marble building in Rome.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

The final resting place of the poets Shelley and Keats.

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

The best preserved Paleochristian basilica in Rome hides a number of oddities and secrets.

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

A Nesting Doll of Churches.

This large, circular tomb is the final resting place of the first emperor of Rome.