A series of abstract, silly sculptures represent the works of a great modern classical composer.

With a history of slaughter, feast, and famine, remnants of the pork industry decorate this area--even its church.

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

Notorious artist squat renovated into legal studios.

This 18th-century sundial was designed to calculate the date of Easter each year.

This mural painted by Keith Haring was done without payment as a gift to entertain the children at the Hôpital Necker.

This grisly effigy displays an early Christian martyr who was skinned alive and beheaded.

A brutalist gem towering over the heart of Milan.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

Now an entertainment complex, the Lingotto building was once an avant-garde auto factory with a test track on the roof.

The intricate geometry inside this Baroque-style dome was designed to create "terror of the human soul."

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

This marine reptile was discovered by one of the 19th century's greatest fossil hunters.

The bones of two medieval royal lions were discovered at the historic fortress.

Eighty million natural history specimens call this gargantuan museum home.

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

Scattered throughout London are ancient remnants of the city's former bounding wall.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

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

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

An architectural oddity hides in plain sight on this iconic London bridge.

Catacombs turned marketplace.