The largest protected conservation area in the Ozarks—a region that stretches into northern Arkansas and southern Missouri.

A likeness of Da Vinci's mysterious painting smiles at passersby from the side of a barn.

A Jurassic artscape composed of transmission casings and other mechanical parts.

This unusual sculpture honors the city's namesake, Octave Chanute, for his pioneering work in early aviation.

This historical marker is all that remains of Octagon City, Kansas, a failed vegetarian utopia.

Don't pass Gas, stop and enjoy it.

It's hip to be square in Iola, home of the largest town square in the United States.

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

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

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.

The only visible remains of this ancient Greek underground temple is its roof protruding from the earth.

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

According to legend, this small island was home to one of the sirens met by Ulysses in the Odyssey.

This ancient city was home to one of the greatest schools of Greek philosophy.

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

The steel cable lets adventurers zoom between two mountain towns at speeds of up to 75 miles per hour.

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

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 tallest statue in Italy is also one of the world's tallest statues of Jesus.

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

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

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