This Peruvian bone silo lined with hanging human skeletons and hundreds of skulls is topped with a remarkable Michelangelo replica.

A house of bones — but nobody is quite sure to whom they belong.

This German bone house contains the remains of some 20,000 souls.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

In 1830, cemetery workers in Cham unearthed a chamber housing thousands of skeletal remains from the 13th century, which can still be viewed today.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

In a small churchyard in Dingolfing, Germany the quaint Schusterkapelle is there to remind you of your imminent mortality.

Structure built from the skulls of vanquished foes.

On the Oregon coast there is a natural hole that seems to be draining the sea.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

A swing to dangle you off the very edge.

A solitary tree has grown up all alone on Lake Wānaka, backdropped by the beautiful Southern Alps.

This impressive collection of rare books on ancient mysticism inspired author Dan Brown.

The haunting ruins of a military fortress turned astronomical observatory sit on a Sarajevo mountaintop.

The latest in a series of long glass bridges suspended at terrifying heights.

A Buddhist temple to honor insects that died for science.

This stunning mass of ice spans 121 square miles and is still growing.

The entire length of the border is marked by a 20-foot-wide slash through the trees.

Built to repay the sins of the father, this church is home to one of the most valuable works of Western art.

This abandoned island off the Venetian coast has been a radical monastery, a political prison, and a secret Nazi base.

Colorful power station with a chimney equipped with a gallery for exhaust monitoring equipment.

A cemetery for Slovenian notables also serves as a popular recreation space.

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

One of the world's oldest universities houses an incredible collection of anatomical models, mummified body parts, and human bones.