Peer Inside the Mysterious Paris Catacombs

These underground tunnels house the remains of over six million people.

10 Survival Stories That Reveal the Power of the Human Spirit

In the face of death, these ordinary citizens did extraordinary things.

The 14 Most Beautiful Underground Caves Anyone Can Visit

Venture below the surface for our planet's most spectacular views.

The Vanishing Crew of the Carroll A. Deering

The crew and their belongings had disappeared for good.

Antarctica’s Outposts: Abandoned at the End of the World

Across the unforgiving landscape of Antarctica are deserted outposts haunted by the ghosts of the past.

6 Famous Explorers Who Vanished from the Face of the Earth

They set off into uncharted territory and were never seen again.