Three bridges straddle a stream, one stacked upon the other.

A rocky sea serpent hides caves, blowholes, and a spectacular natural bridge.

This breathtaking island on Rwanda’s Lake Kivu is a haven for thousands of fruit bats.

This century-old site established by King Mwezi Gisabo preserves the art of Burundi's ancient drum rituals.

Arguing within this idyllic, circular volcanic lake is forbidden.

A remarkably well preserved tower dating all the way back to the Iron Age.

A red sandstone freestanding monolith rises out of the sea in northern Scotland.

This Scottish burial tomb once held hundreds of ancient eagle bones.

Where Aleister Crowley taught magick in "La Chambre Des Cauchemars," his "Chamber of Nightmares."

Conjoined twins Daisy and Violet Hilton were stars of the vaudeville circuit.

A Buddhist shrine in a cave protected by macaques next to dark passages lined with creepy paintings.

This elegant carving of the Buddha guards a small Buddhist temple within a cave.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

Once a bustling fishing port, this semi-ghost town is now more than 90 miles away from the shore.

The Avenue of Mausolea is a series of grand palatial tombs.

This picturesque medieval monastery guards a small trove of historic treasures.

A tower marking the spot where Yugoslavia began its resistance against the invading Nazis stands neglected, but not quite forgotten.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

An ethereal glowing blue ocean cave in Croatia.

This sacred, circular cave is lined with pools so clear and still that it's hard to tell where the water begins.

Freddie Mercury's childhood home is now a monument to the iconic Queen rockstar.

Stay in your own little bubble.

Sitting atop a rock on Michamvi Pingwe beach, this restaurant becomes its own island at high tide.