Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

No one knows how many bodies are in this vault in a Chicago public park.

Fragments of architectural wonders from around the globe are embedded in the newspaper building's walls.

This popular cave pool is truly magical, despite the crowds.

Deep in the Guatemalan jungle stands an ancient pyramid that once marked the reign of a king.

Monkeys inhabit the lush forest surrounding ancient Mayan ruins once considered sacred.

These roaring primates were considered a divine creature in the cosmology of the Maya.

This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

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

These steeply terraced ruins are a stop along the Inca Trail to Machu Picchu.

The mysterious "Candelabra of the Andes" could represent anything from a god's trident to a hallucinogenic plant.

A set of ancient drawings in the desert of Peru that are so massive, many of them can only be fully seen from the sky.

This 16th-century monastery was founded to cloister the daughters of wealthy local families.

What was once a unique system of urban elevators is turning into a mechanical ruin.

A sliver of 19th-century Germany sits on the shore of a Chilean lake.

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

Men in rubber-soled boots serve as your "brakes" on this toboggan ride Hemingway described as "exhilarating."

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

Amsterdam's narrowest house facade is a monument to 17th-century tax evasion.

You can spot this teeny tiny stained-glass window from the Bonifacius bridge.