The ruins of this medieval castle overlook the lake of Piediluco in what was once a sacred forest.

When occupying Nazi troops detonated a mine below, medieval frescoes were revealed in this small cliff-side hermitage.

A colossal aqueduct from the second century B.C., deeply hidden in a gorge on the outskirts of Rome.

A crumbling watchtower and a lighthouse overlooks the site believed to be the Sirens' cliff in the "Odyssey."

A massive marble foot is tucked away in a small alley near the Pantheon.

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

This seventh-century fortification marked the western border of the Lombard duchy of Spoleto.

The ruins of this Roman temple dominate the small city in southern Lazio.

The disputed geographic center, or "navel," of Italy.

One of the four sanctuaries of Rieti's Holy Valley was the site of the first living nativity scene.

Only three columns survive from this ancient temple in the town of Cori.

This stretch of the ancient Roman road is preserved in a valley that witnessed many battles and legendary highwaymen.

A Roman calendar dating to the first century is tucked away in a small town alley.

This massive rock balanced for thousands of years being tossed here during a volcanic eruption.

Hidden in a high mountain cave, this hermitage dates back to the ninth century.

The remains of this medieval Roman road and lookout towers dot the rugged coastline of southern Lazio.

This medieval settlement was abandoned after a series of landslides. What remained was largely destroyed during a mock battle for a WWII film reel.

Magnificent frescoes decorate the interior of this Romanesque church, which also showcases an unusual phenomenon during winter solstice.

Was this cave created by Hercules's wrath, the devil, or volcanic activity?

A monk spent 14 years carving steps through tuff to make this religious site more accessible to pilgrims.

The meaning behind this triumphal Roman arch was a mystery until the early 20th century.

This medieval hilltop village was abandoned at the end of the 19th century, after existing for more than 500 years.

The hilltop town of Segni was once home to an ancient Roman colony and garrison.

Knights Templar are visible inside this stunning Cistercian abbey.