This lab's maddening silence is good for business but bad for sanity.

A grand imperial capital left to fall into magnificent ruin.

These Nubian pyramids are strange and unique, even by pyramid standards.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

These tourist trap caverns are said to be the former home of a legendary Pennsylvania Hermit.

The true age of this ancient stone circle is unknown, but its stunning vista isn't in question.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

This historic observatory was established to keep shipwrecks from littering the Cape of Good Hope.

The atmospheric road was never meant to be so creepy.

A mysterious pre-Incan ruin believed to have miraculous healing powers.

These gutted monastery ruins still stand proudly in the middle of the Italian countryside.

An endless sea of white conical domes.

An Ethiopian "Jerusalem" featuring a church hewn out of a single rock.