Science Ch. - Secrets of the Underground Series 1 (2017) Part 8 American Stonehenge

Secrets of the Underground Series 1

Rob Nelson, an ecologist by trade and an explorer by pastime, travels the country to investigate long-lost, subterranean phenomena

Part 8 American Stonehenge

Investigating the mysterious pattern of rocks at the bottom of Lake Michigan known as Underwater Stonehenge; at the notorious Alcatraz prison, Rob uses state-of-the-art technology in search of rumoured escape tunnels.

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