Ancient Apocalypse

Graham visits ancient mounds in North America and wonders if they contain astronomical significance — or even warnings of an apocalyptic climate event.

All Episodes - Season 1

Episode 1

Once There Was a Flood

Episode 2

Stranger in a Time of Chaos

Episode 3

Sirius Rising

Episode 4

Ghosts of a Drowned World

Episode 5

Legacy of the Sages

Episode 6

America's Lost Civilization

Episode 7

A Fatal Winter

Episode 8

Cataclysm and Rebirth