From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

This luxury shopping lane has been protected by its own tiny police force for over a century.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

The secret cells in the basement of the KGB's Estonian "Grey House" have been preserved as a grim Cold War museum.

This basement museum explores the art and artistry of fascism.

A fascinating insight into daily life in the Eastern Bloc.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

It is against the law to obstruct the view from the top of this English burial mound.

One of Canada's most incredible rare book collections holds hundreds of thousands of gorgeous tomes that the general public can touch.

This top-secret nuclear bunker hidden in a Bosnian mountain has been converted to a modern art exhibition space.

A top secret Cold War bunker hidden beneath a Latvian spa facility is now open for tours.

In this century-old literary safehouse, print is alive and well.