A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

In the days before HD projectors and IMAX, some of the most powerful projectors belonged to planetariums.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Water and windows define this defensive Italian well.

This float factory takes the mask off of Mardi Gras and lets visitors see where the magic happens.

Ancient Bronze Age rampart that was used into the middle ages.

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

Niagara Falls holds a special place in Nikola Tesla's history, so they put a statue on it.

Go inside to really appreciate this 500-year-old technological masterpiece.

Twisted buildings adorn the banks of the Rhine river.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

This former insane asylum now holds a pathological anatomy museum.

A historic presidential getaway on the continental United States' southernmost island.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

Ancient Peruvian fertility temple or modern money-making hoax? Either way these monoliths still look like penises.

Baroque celebration of the end of the Great Plague of Vienna.

Jesus' footprints and the first catacombs in the world.

Death rituals and sacrifice inside a Peruvian megalith.

Pre-Incan aqueduct amidst a stone forest in Peru.

A centuries-old church stands as a testament to Boston's "father of architecture."

A former waterfront market is now in the center of town due to some interesting Boston engineering.

A monument celebrating the idea of reaching inaccessible places.