Architectureal fantasy quarter of Rome.

Stare out over the lagoon and beyond from this 10th-century campanile on the island where the city of Venice began.

Originally a leper colony, the island is now an Armenian monastery that's home to an incredible manuscript library and eclectic museum.

The fairy tale castle of the "fairy-tale king."

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

A traditional American farmhouse plopped in the middle of a Piccadilly courtyard.

This hidden rooftop garden in downtown London offers a quiet respite from a bustling city.

Since 1874, this macabre collection has developed into a museum devoted to Scotland Yard's mementos of dastardly deeds.

A sculpture of a famous ape who was once a beloved household name in London.

This Viking gravestone carved in a rare runic style was dug up from a London churchyard.

The "lost friend” is the most famous of the six moai statues that were removed from Easter Island.

This secluded walkway overlooks a magnificently wild London green space.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.

A Roman spa buried deep beneath the City of London.

This museum tucked below a charming cafe gives a brief snapshot of photographic history.

This 1920s Dutch barge is now a floating bookstore.

An small and easily overlooked archaeology museum chock full of Egyptian artifacts.

A collection dedicated to the treatment of disease, held in London's oldest hospital.

Remnants of a Victorian garden feature sitting in public woodland.

Rebuilt remains of a temple to Roman god Mithras.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."