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

Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

A Portuguese Jewish cemetery filled with stunning grave monuments that date back to 1614.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This inn of the court provides a fascinating window into London’s legal and architectural history.

This hydraulic power system in London was, at one time, seen as a rival to electricity and the last of its kind to shut down.

Chelsea's soldiers were given strict orders when crossing this historic bridge.

3,000 family pets and military animals are buried in this London graveyard.

The final resting place of a German diplomat's beloved companion.

The remains of a historic football stadium that once hosted 50,000 spectators.

The pockmarks across the building's facade are remnants of the Blitz.

A tribute to the intrepid explorer and his crew who perished in terrible conditions on an ill-fated expedition to the Arctic.

This medieval church tower has maintained its clockworks since the 16th century.

This peeling mural of Adam and Eve was inspired by the greenhouses at Kew Gardens.

Victorian-era Londoners really wanted to believe this 17th-century cistern was actually an ancient artifact.

Historic church where a number of Shakespeare's actors are buried.

A monolithic monument in Greater London.

It's a mystery why these remains were found with no traces of their bodies in sight.

This knockout museum lies in a sleepy corner of London.

Colorful murals by Jean Cocteau hide within this peaceful London sanctuary.

The plunge pool is a surviving relic of a rowdy royal residence.

This historic building displays the remains of a victim of the devastating 14th-century plague.

The commemorative stone column conceals a secret laboratory.