5:00 AM: Secrets Of The Underground (S1 E2) (S1) | Discovery Science | 10/23 2025

5:00 AM - 6:00 AM

4 hours

Secrets Of The Underground « at 5:00 AM on Discovery Science

Episode 2

Broadcast info
Published:	2017
Episode:	Mystery Of The Serpent Mound

Rob Nelson investigates mysterious tunnels under Denver's airport. Plus, in Ohio he tries to uncover the secrets of a giant serpent-shaped mound.

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