Perhaps the most spectacular grotto along the Algarve coastline.

A chunk of the "true cross" is held in this small Portuguese church where modern day exorcisms are said to be common place.

An abandoned mine now resembles a post-apocalyptic landscape of derelict buildings and blood-red pools of water.

This small chapel is built of human bones and decorated with a golden skeleton.

Dead weights honor the dead of Portugal's fishing industry.

The sole surviving relic of the San Francisco neighborhood cobbled together from old horsecars and streetcars.

Once the most densely populated place in the world, this island is now a ghost town.

Steaming blood-red hot spring from hell.

The world’s first hotel to be run by robots.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.