Europe's second largest ossuary wasn't discovered until 2001.

This small chapel is built of human bones and decorated with a golden skeleton.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

An Austrian house of bones filled with hundreds of intricately painted skulls.

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

A church of bones, decorated with 40,000 human skeletons.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

David Sedaris called it "The greatest shop in the world."

Underwater art project will double as a massive artificial coral reef to help regenerate the damaged ecosystem.

Tropical paradise strewn with hundreds of World War II wrecks.

Stunning wetlands ablaze with pink lotus flowers.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

Known as the wettest place on earth.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

Small on the outside, big on the inside, this church is an astonishing act of visual deception.

Cliffs that hold fossils, including the earliest known reptile, dating back more than 300 million years.

Known for the tunnel that leads visitors to the water.

The single richest source of elemental discoveries in the world.

Home to the deepest rift anywhere on Earth.

The only road through the heart of Glacier National Park.

Every year, over 25,000 monarchs overwinter in Pacific Grove.

Two rocks in a perpetual kiss and one of "the most romantic spot in America."

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.