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Cities of the Underworld Season 4 Episodes

Season 4 Episode Guide

8 Episodes 2021 -

Episode 1

Mayan Apocalypse

Tue, Sep 7, 2021 62 mins

Don Wildman searches for clues pointing to the true fate of the once-mighty Mayan empire.

Where to Watch
Cities of the Underworld, Season 4 Episode 1 image

Episode 2

America's Military Underground

Tue, Sep 14, 2021 58 mins

Don explores top-secret military and government tunnels and looks into classified technology that could be used to build entire cities.

Where to Watch
Cities of the Underworld, Season 4 Episode 2 image

Episode 3

Murder Tunnels

Tue, Sep 21, 2021 62 mins

Don uses brand new mapping technology to expose the dark and deadly uncharted spaces beneath American cities.

Where to Watch

Episode 4

America's Ancient Ancestors

Tue, Sep 28, 2021 56 mins

Don goes deep beneath the great lakes in search of evidence of a mysterious, cave-dwelling society that may have been the first people to reach America.

Where to Watch
Cities of the Underworld, Season 4 Episode 4 image

Episode 5

The Pirate Queen's Lair

Tue, Oct 5, 2021 62 mins

Don explores newly discovered ruins and caves in Croatia as he uncovers the true story of a formidable queen who dared to defy the powerful Roman Empire.

Where to Watch
Cities of the Underworld, Season 4 Episode 5 image

Episode 6

Templars and the Founding Fathers

Tue, Oct 12, 2021 62 mins

Don goes deep beneath a Knights Templar stronghold in Turkey to explore a provocative theory that may link the fabled secret society to the founding fathers of America.

Where to Watch
Cities of the Underworld, Season 4 Episode 6 image

Episode 7

Secrets of the Ancient Metropolis

Tue, Oct 19, 2021 62 mins

Don explores the massive underground cities in the mountains of Turkey that may have been home to the first civilization on Earth.

Where to Watch
Cities of the Underworld, Season 4 Episode 7 image

Episode 8

The Lost Aztec Colony

Tue, Oct 26, 2021 62 mins

Don follows the clues hidden underground as he searches for evidence of 10,000 Aztecs who fled Mexico and disappeared somewhere in America.

Where to Watch
Cities of the Underworld, Season 4 Episode 8 image