Sweden's first nuclear reactor, R1, can be visited 25 meters underground.

Crumbling ruins mark the site of a couple's grisly murder in the woods.

Just a few miles from downtown Atlanta is a trail covered in a crazy collection of outsider art.

Tour the sci-fi-esque reality of governmental disease management.

Secret gardens just a few miles from downtown Atlanta.

Mai Tais and Navy Grog served up in one of the original tiki bars.

An underground magnet for ever-changing street art.

Scattered around Atlanta are little doors with big charm.

Outsider art or homage to aliens?

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

The smallest country in the world.

Once a farm where patients tilled the soil, this asylum lost its workforce when overmedicating became common practice.

A brick foundation and piles of listing building materials are all that remains of this World War II POW camp.

A miniature Italianate fantasy village on the coast of Wales and the set of ITC classic "The Prisoner."

A vortex fountain that seems to rise out of the ground.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

A hundred copies of Antony Gormley's naked body stare out across the water.

A modern English garden of eccentric beasts, follies, and oddities.

This beautiful "lagoon" is actually a toxic soup filled with cars, carcasses, and trash. When warnings couldn't stop people from going for a dip, the town dyed it black.

A metal tree emits eerie, melodic notes on top of Lancashire's Crown Point.

Once thought to be the mysterious work of a witchy prophetess, a well with unusual properties turns objects into "stone".

An island filled with hundreds of hanging, decomposing, decapitated dolls.

Museum dedicated to the terror regimes of Hungary.

Electrical curiosity museum housed in an old transformer station.