An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

The burial place of an obscure North African saint was turned into a macabre body preservation factory for the 17th-century Neapolitan elite.

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

Walk through spectacular aisles of hanging meat and wagon wheel–sized cheese at the world's largest wholesale food market.

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

Sandstone rock formations that look like they belong on the cover of a progressive rock album.

Nestled in the hills of Tuscany are gorgeous, multicolored hot springs.

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

One man has installed bathtubs into the Utah desert floor to harness the powers of a natural hot spring.

Even in death, he's still your huckleberry.

This spectacular track has run continuously since 1882.

These fantastically named natural pools look like something out of a Scottish myth.

An ancient Scottish rock formation said to be the gravesite of a giant remains ensconced in legend and intrigue.

Wander among the abandoned ruins of this once-powerful medieval town.

Caves famous for the dragon-slaying saint who lived there.

The patron saint of spinsters grasps a container of dried blood.

This geothermal hot spring hides beneath a slowly growing mineral dome.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

A house of bones — but nobody is quite sure to whom they belong.

The remains of this ornate chapel now act as a portal to a cramped French cemetery.

An isolated 17th-century chapel on a remarkable site once dedicated to Celtic sun worship.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

An ancient ossuary in Rouen.