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From the smallest cell to the solar system, Science is an odyssey of scientific facts, investigations and breakthroughs.

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A forgotten world of ancient underground passages and medieval engineering lies hidden beneath the town of Exeter, England; experts investigate and reveal how this ambitious tunnel system was the result of one of the deadliest epidemics in history.

Underground Marvels

Medieval Maze of Secrets

Subterranean military fortresses situated on the southern coast of Ireland have protected against enemy invasion for over 400 years, and now, experts investigate how this powerful stronghold transformed into a brutal and terrifying prison.

Ireland's Underground Alcatraz

An unprecedented landslide unveils a hidden world beneath a picturesque town in northern Italy, and now experts investigate this vast network of tunnels and passageways that stretch 300 feet underground to reveal the city's subterranean past.

Italy's Subterranean Secret

A decommissioned missile launch facility in Kansas remained one of the best kept subterranean military secrets of the Cold War; experts reveal how this abandoned underground complex transformed into a state-of-the-art survival bunker.

Subterranean Silo Survival

Buried nearly a mile beneath the Black Hills of South Dakota is a cutting-edge laboratory at the forefront of astonishing scientific research; experts reveal advancements engineers achieved more than a century ago that keep it operating today.

Buried Lab of the Black Hills

The longest known cave system in the world spans hundreds of miles beneath the hills of Kentucky, and containing prehistoric artifacts and ancient human remains, experts reveal a subterranean mystery that may have changed the course of U.S. history.

Mystery of the Kentucky Cave

Hidden beneath the town of Ramsgate, England, lies a hidden network of over three miles of air raid tunnels; experts investigate and uncover an extensive WWII bomb shelter that became a permanent refuge for many civilians after a devastating attack.

Murder Raid Tunnels

Deep beneath the streets of Cincinnati lies a network of deserted tunnels and caverns that contain a remarkable history of the city's origins, and now, experts investigate to reveal who built this underground labyrinth and why it was abandoned.

Cincinnati's Secret Caverns

Descending more than 200 feet beneath the Arizona bedrock lies the largest dry cave system in North America; experts explore this vast subterranean network to reveal the mysteries and undiscovered treasure that remain hidden within its walls.

Grand Canyon's Lost Treasure

The top-secret construction of a massive nuclear bunker remained concealed under a palatial West Virginia hotel for decades; experts reveal how this vast subterranean structure was one of the most closely guarded Cold War secrets in U.S. history.

Hotel Bunker of the Apocalypse

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Uncovering subterranean phenomena around the globe, their impressive stories, unique origins, essential roles throughout history, and the secrets they keep hidden deep below.

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From the smallest cell to the solar system, Science HD is an odyssey of scientific facts, investigations and breakthroughs.

S2 E10 | Medieval Maze of Secrets