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S4 E3 12/14/19

Wonders of the Underworld

New discoveries reveal various deserted, underworld engineering projects -- from a terrifying sea fortress to a strange complex of towers in a forest of ice. Experts explain why they were built and why they were eventually abandoned.

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The Latest

Discovery Exploration

Seasons

Episode   1

American Atlantis

Episode   2

Curse of Cliff City

Episode   3

Jungle of the Damned

Episode   4

Kingdom of the Vanished

Episode   5

Journey to Outcast Island

Episode   6

Haunting of Heartbreak Castle

Episode   7

The Devil's Prison

Episode   8

Curse of Satan's Catacombs

Episode   9

Swamp of Despair

Episode   10

Hell on Blood Island

Episode   11

Florida Doomsday Castle

Episode   12

End Times on Lake Michigan

Episode   13

The Thing on Hell Mountain

Episode   14

Towers of Blood

Episode   15

The Killer in the Castle

Episode   16

Nightmare at Fort Paranoia

Episode   17

World's Strangest Disaster Zones

Episode   18

House of Horror

Episode   19

Anarchy on Ireland's Alcatraz