Jesus' footprints and the first catacombs in the world.

2300-year-old Roman road connecting the empire.

One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

The ruins of a medieval village that was abandoned after a 19th-century inferno.

The underground sanctuary of a mysterious ancient Roman religious cult contains an exquisite traditional fresco.

This medieval Italian town is a sheer (and beautiful) cliffside defense.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

Crossing this suspension bridge feels like walking through the sky, a fitting tribute to the head of the Apollo program.

An Italian hillside ghost town.

A beautifully well-preserved ancient Roman villa.

Beautiful views and Roman-style statues on the Italian coast.

This Pennsylvania cave holds evidence of the oldest known inhabitants of North America.

This tiny business claims to be "the smallest pub on the planet."

A remarkable time capsule of American manufacturing deep in Maryland coal country.

Overshadowed by quilts, the artistry of these patterned textiles went underappreciated for too long.

More than a century of radio history is told in these displays.

The early American colonists were such ferocious drinkers the law actually required every town to have a tavern.

The mysterious headstone of an unidentified bank robber was seen visited, every year, by a woman in black.

Locals purchased this abandoned quarry in order to make sure it continues to be overgrown.

This giant Massachusetts sycamore is said to hold the dubious distinction of being the "widest tree East of the Mississippi!"

The ruins of a Massachusetts prison farm can still be found crumbling the woods of a state park.

All that remains of this Massachusetts town, demolished in the name of progress, is a stone marker.

The walkable ruins of an 19th century hotel, destroyed in a horse cremation gone wrong.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.