Episode
E1Capone's Escape TunnelsFeb 14, 201760mE2Mystery of the Serpent MoundFeb 21, 201760mE3America's Buried MassacreFeb 28, 201760mE4Rocky Mountain MonstersMar 7, 201760mE5Great Lakes Bermuda TriangleMar 14, 201760mE6California's Hidden DoomsdayMar 21, 201760mE7Secret History of the New WorldMar 28, 201760mE8American StonehengeApr 4, 201760m
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Secrets of the Underground
20176
RealityDocumentary
Released
Feb 14, 2017
Country
United States
Production
Science Channel
A search for an underground escape route said to have been used by Al Capone. Also: who or what built earthen mounds in Washington state.