Nestled in the mountains of Portugal is a tiny village made almost entirely of schist.

This amazingly well-preserved villa just outside Pompeii boasts rare examples of ancient Roman paintings.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

The pile of books behind the dignified writer gave the statue a most undignified nickname.

Cabaret where the show girls are all androids, and the patrons couldn't be more pleased.

Not quite the menace it once was, this monster still has some chops.

A magnificent, long-abandoned castle built in the wake of the reconquest of Spain.

An iconic view point of the Sea of Galilee offers a look into Israel's past.

Explore the quarry where the marble was sourced for Michaelangelo's David.

A 16th-century horror show built in a lovely Italian garden.

An ancient underground cultic temple where sunlight penetrates on the summer solstice.

Something's watching you.

These "anatomical machines" are only one of the many strange items in this Italian crypt.

A harrowing trail up a mile-high mountain.

A total of 999 stairs lead visitors through a massive hole in a mountain known as the Gateway to Heaven.

For those with no fear of heights: a skywalk 4,700 feet up on a Chinese mountain.

Macabre astrological automaton clock dating to the late 1400s.

The field of tiny caves that mark this Chinese cliffside are each their own historic Buddhist temple.

The bluer than blue waters in these natural Israeli caves are reached via the world's steepest cable car.

This nostalgic Russian museum is full of USSR cultural artifacts from the 1970s and 80s.

Fortified homes of highland warriors that are still in use today.

This neon lit Georgian cave claims to hold the boulder Prometheus was chained to.