The sunlight passing through the opening of this huge cave system creates a magical effect.

Though they look like Hobbit houses, these semi-underground stone structures were built for winemaking.

Its look is severe, but its location, isolated on a hill in the middle of the countryside, is particularly scenic.

An impressive bridge over a ravine also served as an aqueduct.

People have been living in the cave houses on this Italian hillside since the Neolithic era.

One of the few places of its kind, this space research center sits deep in the countryside of Matera.

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

Ride a boat through this magnificent underground world, which now doubles as a theater.

Also known as the Temple of Poseidon, this is one of the best-preserved Greek temples in the world.

An abandoned quarry hides an open-air gallery of huge sculptures, some made from the rubble of 9/11.

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

An Italian hillside ghost town.

Though an earthquake destroyed this village in 1980, one former resident still walks its streets every day.

The pristine waters crossing this forest form a hidden waterfall among the dense vegetation.

A small thermal park among the mountains of Southern Italy features a surprising piece of modern art.

This small but lovely sinkhole lake is the last remnant of a great prehistoric water basin.

The oldest scientifically dated tree in Europe lives on a remote cliff.

This crystal clear water basin feeds the Lao river and powers a hydroelectric power plant.

Constructed during the 1960s, this bridge is still the highest in Italy.

A mountain cave is the site of archaeological findings and Paleolithic rock art.

The abandoned ruins of a failed resort hide on this verdant, picture-perfect island.

The ruins of this medieval castle now stand as a monument against all wars.

A single column facing the sea is all that's left of one of the most important temples of Magna Graecia.

This church carved into the rocks is full of enchanting stone statues.