The remains of a 1st-century aristocratic Roman town house featuring beautiful well-preserved mosaics.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

This prison on the Maltese island of Gozo is almost 500 years old, and they have the graffiti to prove it.

This subterranean necropolis holds three floors of antler-dug grave caves.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

This Stone Age solar temple aligns with the sun on each equinox and solstice.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

The medieval woodcut-style artwork chronicles life in medieval London.

These mysterious Viking chess pieces spent centuries hidden on a remote Scottish island.

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

Charles Babbage's proto-computer, painstakingly brought to life.

The library houses an incredible collection of some of the world's most impressive books and manuscripts.

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

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

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

Hidden beneath the streets of London is a secret subway that only carried mail.

Eighty million natural history specimens call this gargantuan museum home.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

The historic site where Queen Elizabeth I once gave a searing speech.

The only museum in the world dedicated to preserving the life and work of American comedian and entertainer, Phil Silvers.

All that remains of the medieval palace of the famous "Black Prince."

Built in the 1300s, this magnificent building that hosted England's kings and queens transports you to the Middle Ages.

One of these two land speed record-breaking vehicles went so fast it shattered the sound barrier.

All that remains of the only English cathedral destroyed in the Protestant Reformation.