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Mystery of the Serpent Mound

Rob Nelson explores mysterious tunnels beneath Denver's airport, capitol building, and downtown to investigate rumors of a secret organization. Also, the ancient secrets of a giant mound shaped like a serpent are investigated.

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  • Originally Aired February 21, 2017
  • Runtime 45 minutes
  • Content Rating United States of America TV-PG
  • Network Science Channel
  • Created March 8, 2017 by
    Administrator admin
  • Modified March 8, 2017 by
    Administrator admin