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

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

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

This large, circular tomb is the final resting place of the first emperor of Rome.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

A beacon atop a downtown building provides Bostonians with weather forecasts and baseball news.

Created by a local artist, these quirky sculptures each have their own names and personalities.

The Boston square dedicated to the dark poet who was born nearby.

Decorated by local artists, the city's utility boxes have become three-dimensional canvases.

A herd of colorfully painted bovine statues can be found in the middle of "cowtown."

Take a hike to this remote, scenic tea stop in the Canadian Rockies.

Few other hotels can rival the grandeur of the Castle in the Rockies.

The famous sculptor left his mark on this Italian wall in an internationally protected example of street art.

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

Once a slice of Cold War-era military history, this museum is finding its future in the stars.

A museum chronicling pioneer life constructed over Interstate 80.

One of the world's earliest skyscrapers.

The first car-centric shopping plaza in the U.S. brought a little bit of Spain to downtown Kansas City.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

Speak to a companion on the other side of the room loud and clear through this architectural anomaly.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.

One of the first intercontinental ballistic missile sites in the United States.

More than 7,000 gallons of water pour over these cascading red quartzite waterfalls every second.

Dedicated to the history of the 1,000 nuclear missiles that once covered the Great Plains.