A grand imperial capital left to fall into magnificent ruin.

Hellam Township is reputed to feature seven remote gates, which when passed through in the right order, open an entrance to hell.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

These azure waters were thought to lead to the Mayan Underworld.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

This Costa Rican topiary park is a surreal garden of unearthly delights.

This historic black and white monastery is one of Bulgaria's architectural jewels.

The world's greatest slide descends 18 stories from this looping mountaintop viewing platform.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.

Enchanting cave with a river crashing through the roof.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

Spanning the El Chorro gorge, this pathway used to be one of the most dangerous crossings in the world.