This Luxembourg cave is covered in cryptic looking marks left by mining activity.

The last bastion of Roman presence north of the Alps looms over a German town.

A tiny chapel clings to a precipice above Germany’s gemstone capital.

The world's longest known cave system.

Planes, trains, and automobiles have all been sunk as attractions at this Illinois diving spot.

Home of an evil witch famous within southern folklore.

Crumbling Kennedys and a decaying Tecumseh are just some of the haunting remains of one man's cement art trail.

Hiding behind a grocery store is a spectacular cavern carved as part of an old limestone quarry.

A key producer of charcoal iron in the early 1800s, the structure still stands today.