An old quarry transformed into a recreational and cultural space.

The largest cave on the island of Menorca was likely the site of Iron Age rites and rituals.

The spectacular Roshen Fountain show lights up the night sky all summer long, until it "hibernates" under the ice waiting for spring to come.

If you can look past the nearby sewer pipes, this urban sinkhole grotto is a mini-paradise.

During its heyday, the massive estate boasted its own railroad station and post office.

Repository for more than 22 million pickled specimens.

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

The signs of a long buried road can still be found hidden beneath a London sewer grate.

Angels, demons, and tortured souls on a giant wall mural in a little church.