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

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.

Breathtaking and huge 430 year old maps of Italy.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

This small condiment museum makes all manner of mustards with a 200-year-old mill.

A stonemason's hilarious revenge came in the form of this peculiarly positioned gargoyle.

These paved rills bring freshwater into Altstadt and could spell wedding bells for whoever stumbles into the waters.

Flowers have mysteriously appeared on her effigy every day for the last 150 years.

Soaring over 6,000 feet in the Bavarian Alps, this beer garden was once Hitler's 50th birthday present.

This skeleton-filled altar piece served as a backdrop to one of the most iconic scenes in "The Sound of Music."

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

Trick water gardens from 1619 featuring a 200 piece mechanical theater powered by water.

These unusual rooms on wheels are holdovers from the 1960s.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.