One of the deepest indoor swimming pools in the world.

From Tintin to the Smurfs, Europe's greatest graphic icons are celebrated in a grand Art Noveau gallery.

Climb inside an iron crystal magnified 165 billion times its normal size.

Medical history with an amazing, if frighting, collection of wax diseases on display.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

The Devil’s own choice when he needs a drink in Brussels.

The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.

Part modern art project, part traditional chapel, this see-through church is only substantial from the right angle.

This ghost town in Belgium will lose its street art when it ceases to exist.

This abandoned Slovenian military barracks has become a punky-political art squat.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This one-time health resort was used by aristocrats around the world.

Despite being pillaged and destroyed a number over times down the centuries, this historic church still sort of stands.

A sinuous path among steep cliffs creates a stunning sight in southwestern Serbia.

A Serbian church lit by chandeliers made of weapons.

This spaceship-like Serbian monument reaches for the stars in celebration of the fallen fighters of fascism.

This memorial park stands on the site of one of the largest mass executions of the Second World War.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

Structure built from the skulls of vanquished foes.

An unusual cave filled with rare alien-looking aragonite formations.

A unique hotel for the artistic soul.

After 11 years of reconstruction work, Slovakia's finest hilltop chapel complex is finally reopen to the public.