If there's another drive-through golf-cart bar in a bat-filled cave on top of a mountain, we don't know about it.

Sofia's legislative center is continuously reinventing itself.

"Holy Wisdom" overlooks the city that became its namesake.

A quirky roadside sign was the subject of a years-long legal standoff over highway right-of-way clearances. 

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

A local student's chance encounter with Keith Haring led to the creation of one of Europe's largest murals.

2300-year-old Roman road connecting the empire.

Breathtaking and huge 430 year old maps of Italy.

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

This small church was constructed over the ruins of three temples dating to the Roman Republic.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

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

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

These ruins of a Phoenician sanctuary in Sicily have a dark history.

A never-inhabited village that was built as part of Mussolini's agricultural reforms.

According to Greek mythology, this natural spring is the home of a freshwater nymph.

These temples are among the oldest free-standing stone buildings in the world.

Despite the name, these small saltwater swimming pools have nothing to do with the Romans.

A centuries-old forgotten underworld lies beneath Malta.

Both the World War II Allied Forces and NATO have used this modern bunker underneath Malta’s capital.

The world's only teal arches exist in a city that cares more about its aesthetic than an Instagram influencer.

Originally conceived as part of a proposed Arizona State Capitol building in the 1950s, this structure built in 2004 stands as a monument to the architect's legacy.

A geological mystery on Camelback Mountain.