Secrets of the Underground Season 1 Episode 2 Mystery of the Serpent Mound 2017
4.3/10 by 3 users
Rob Nelson explores mysterious tunnels beneath Denver's airport and capitol building to investigate rumors of a secret organization operating below. In Ohio, he tries to uncover the ancient secrets of a mound shaped like a serpent.
- Released: 2017-02-21
- Runtime: 60 minutes
- Genre: Reality, Documentary
- Stars:
- Director:
