A huge musical instrument played by the ocean.

This 19th century mansion façade adorned with immigrant patriotism is a symbol of Louisville’s history.

This morbid, delightful curiosity shop offers everything from animal bones to human teeth.

A group of artists transformed this desolate city alleyway into an outdoor gallery of street art.

This holy goods emporium is where priests go for a little retail therapy to outfit their churches.

An off-the-beaten-path place to literally hang beneath Milwaukee's Holton Street Bridge.

These Stolpersteine located in Spain honor Republican soldiers who perished at the hands of Nazis after the fall of France.

This amazingly well-preserved villa just outside Pompeii boasts rare examples of ancient Roman paintings.

The walls and streets of the ancient city are peppered with penises.

Ancient snack bar of the Roman Empire re-opened.

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

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

This ancient Egyptian obelisk still bears the wounds of World War I.

The ritual has been performed uninterrupted for nearly 700 years.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

An unusual round church in London with a Templar past.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

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

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."