A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

At night, bats patrol this magnificent 18th-century space in search of book-eating pests.

A fortress off the West coast of Portugal that dates back to 1502.

On a trail in Portugal's Barão de São João National Forest, a pile of faces look up at hikers from the forest floor.

Perhaps the most spectacular grotto along the Algarve coastline.

This unassuming chapel in Portugal plays host to a ghoulish collection of bones.

The mountaintop inspiration for Umberto Eco's "The Name of the Rose."

A magnificent waterfall is also home to the remains of a Roman hydraulic engineering system.

Open for a weekend once a year around October it houses a fascinating collection of unique Victorian preserved and stuffed animals.

Dedicated to the god Dionysus, this theatre was used for both musical and theatrical performances.

This open air archeological site houses almost as much wildlife as it does classical religious artifacts.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.

Carefully reconstructed after the Bosnian War, this 16th-century bridge stands as a symbol of the country's enduring multicultural heritage.

Former military fort and site of untold horrors during WWII, this island may become the Adriatic's next luxury resort.

A beautiful mountaintop mausoleum devoted to a Montenegrin icon can't seem to make everyone happy.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

The only known mosaic depicting the Greek god of sleep, Hypnos.

A tiny church on a man-made island in the Adriatic.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

A World War II evacuation tunnel turned into a history display of Croatian state and people.

Where the lovelorn find a home for their sentimental keepsakes.

This only museum in the world dedicated solely to mushrooms.

The remains of a sunken military ship wreck visible through clear water.