The world's only museum devoted to the wonders of fluorescence.

This 1920s Amsterdam neighborhood was built as a giant experiment in concrete construction.

A lecture hall sink once used by Einstein and other noted physicists is now regarded as a strange science relic.

Peek through a transparent pyramid and drink in the mountain made of books.

This abandoned secret city is a crumbling wonderland of Soviet ruins.

The gutted remains of this Estonian mansion are a monument to a tragic love.

Mysterious craters may have been home to an ancient cult.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

A haunting collection of the vanished and disappearing natural world.

Notorious artist squat renovated into legal studios.

A mechanized clock where a man fights off a dragon, crab, and rooster.

Following the trail of an old metro line, this scenic path is haunted by a creepy spriggan statue.

The mouldering remains of a disgraced British children's icon are hidden in the brush of a public park.

A genuine Little Shop of Horrors.

Repository for more than 22 million pickled specimens.

An abandoned tank sits in an empty London lot as a symbolic middle finger to local city planners.

A comic book store that puts the marvel back in marvellous.

Abstract dinosaur models in London.

The remains of Crystal Palace Great Exhibition of 1851.

Visit on a Sunday morning to see some killer tricks.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

The biggest and deepest Cold War bunker open to the public can be found in southeast England.