One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

An architect's childhood fantasy treehouse made real.

The Pope’s secret escape route.

In Florida, these naughty monkeys live on their own mini-monkey Alcatraz.

Ruins of an old sugar mill sitting quietly next to a park in rural Florida.

A lone gunner's station is all that remains of a replica Spanish Fort in Florida.

This grand Spanish-Cuban restaurant has been serving customers for more than a century.

A Circus legend leaves an unexpected endowment.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

This statue is the only female representation of Rome's "talking statues."

In the early Roman Empire, people deemed traitors and criminals were tossed to their deaths from this rock.

This ancient Roman prison is decorated with an upside-down cross not as blasphemy but as saintly tribute.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

St. Francesca Romana, patron saint of drivers, resides in the church she founded.

This ancient market is often referred to as the oldest shopping mall in the world.

This Italian stadium makes liberal use of fascist statuary to evoke classical sporting arenas.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

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

Legends surround an ancient tree trunk riddled with nails for good luck.

A small marionette collection located within the dark cellars of an 11th-century Austrian castle.

Go surfing on this urban wave, "hacked" by local surfers.

The world's oldest known salt mine.