A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

One of the world's heaviest musical instruments towers within a popular urban park.

A fascinating insight into daily life in the Eastern Bloc.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

A marine aquarium with an astounding variety of fish hides in the basement beneath the famous Palm House.

These docile dragons are ideal inhabitants for the conservatory greenhouses.

A measuring mishap led to these artificial stone ladies losing their stomachs.

London's marvelous wildfowl reserve along the Thames.

An exercise in radical design and social living that became the epicenter of Soviet spy networks in London.

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

The fences outside some of South London's estates are made from recycled World War II stretchers.

This beautiful deer park was built so King Charles I and his court could go hunting while escaping a deadly plague outbreak.

An unusual ode to the late Irish playwright, complete with a squiggly bust and coffin-shaped bench.

A labyrinth hides in plain sight at each of the city's 270 Tube stations.

The Tudor-style cottage in the middle of the square is not quite what it seems.

A unique tribute to the millions of animals who served and died for the British military.

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

The secret wartime bunker built on the platforms of an abandoned Tube station.

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

A little slice of Japan and its aesthetics in London's Holland Park.

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

A museum wholly devoted to juvenescence.

Ship-sized kinetic sculptural fantasy.

A plaque hangs near the execution place of the Scottish Independence leader famously depicted in "Braveheart."