Stockholm's deepest subway station is also a stunning ecological wonder.

This gem from the industrial age helps visitors and residents alike traverse hilly Stockholm.

An ancient Viking runestone hidden in plain view in Stockholm's old town.

A plaque marks the house in Stockholm where the French philosopher René Descartes lived up until his death.

Stockholm's narrowest alley is barely over two feet wide.

A man has revenged his true love's betrayal through tears and stone genitalia.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

This still-celebrated home was a radical architectural experiment in 3D De Stijl.

The 20-mile causeway that separates the Netherlands from the sea.

A Belgian self-built tower inspired by the Bible and ancient civilizations.

A maze of crosses marks the jumbled divide between the Netherlands and Belgium.

This memorial museum chronicles the apocalyptic destruction of the First World War.

Medieval town turned hippie commune, once home to the secret foreskin of Jesus Christ.

A young Italian couple has been locked in an embrace for over 6,000 years.

The skulls and bones of thousands of soldiers line the walls of this small Italian chapel.

The bones of some 7,000 soldiers killed in the historic Battle of Solferino are stored here.

This breathtaking monastery was established by Saint Benedict himself 1,500 years ago.

This is not only one of the oldest collections in Europe, but also possibly the most beautiful.

This aging storage facility is the world's largest brick warehouse.

The tower was originally used as a chimney for the waste incinerator of St Johns Precinct and Market.

Gutted during the Liverpool Blitz, this architectural husk has been left destroyed in honor of the dead.

The Liverpool street made famous by the Beatles is real.

The quiet field that inspired one of the most famous songs of all time.

The medieval prince founded the first library in Ukraine at Saint Sophia's Cathedral where he was interred.