A fiery crater has been burning in the Karakum Desert since 1971.

A dormant lightning machine equal to all the power in Russia.

The sign at the garden gate reads: "These Plants Can Kill."

Puzzles within puzzles hide a golden treasure in this hedge maze.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

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

The only university zoological museum in London houses extinct animals, bizarre natural history specimens, and a Micrarium of microscopic creatures.

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

Humble beginnings for one of the world's most famous scientists.

A pub that is literally in the middle of nowhere, but continues to do business.

A midnight snack that lights up the night.

A house of bones — but nobody is quite sure to whom they belong.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

The world's largest solar furnace uses 10,000 mirrors to concentrate the sun's rays to generate power.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

This attraction was abandoned after the Chernobyl disaster.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

This impressively complicated radioastronomy research center was once a tool of Soviet spies.

Mysterious craters may have been home to an ancient cult.

Man-made mineral caves house massive bat colony.

Beyond the usual stories that attend old prisons, this one has deep bloody undercurrents.

A particularly creepy abandoned hospital that sparks interest for lovers of the supernatural.

Outstanding collection of 19th century medical instruments includes a life-size figure cast from as many as 200 cadavers.