Last episode
America's Hidden Training Camp
s04e09 · 2025-08-07
Running · US
Mysteries of the Abandoned: Hidden America
Discovery Documentary
What it is
Scattered across the United States are abandoned structures, forgotten ruins of the past, and monuments to a bygone era. Each one shines a light on the story of this land and its people, revealing the secrets of a hidden America.
Episode highlights
Next episode
None captured
Episode guide
9 this season · 30 totals04e01 The Cult Hotel 2025-04-24 03:00
The Cult Hotel
A worldwide communications facility is taken over by a dangerous cult, a secret arsenal harbors the most destructive weapons ever known, and an ordinary inn has a surprising history.
s04e02 Hunting for the Ship of Gold 2025-05-01 03:00
Hunting for the Ship of Gold
A crew searches for a shipwreck loaded with gold and sets off a long legal dispute, a lavish complex in the Catskills attracts many of America's great comics, and a zoo full of metal sculptures marks the spot where war once came to Colorado.
s04e03 America's Gun Factory 2025-05-08 03:00
America's Gun Factory
A company town produces weapons that transform the Wild West; a building complex revolutionizes communications on this world; an old mine bears the scars of a deadly labor conflict; a forest hides the remains of a socialite's mansion.
s04e04 Nazi Secrets in the Empire State 2025-05-15 03:00
Nazi Secrets in the Empire State
A strange structure in New York becomes a testing ground for Nazi technology; a thriving amusement park is laid to ruins by an unstoppable force of nature; an island becomes a major player in a controversial industry.
s04e05 The Vermont Doomsday Gun 2025-05-22 03:00
The Vermont Doomsday Gun
A research facility (Space Research Corporation in Jay, Vermont) spawns new technology with earth-shattering implications; a coastal haven for African Americans (American Beach, Florida) changes the nation; a forgotten fortress (Fort Greene at Point Judith, Rhode Island) fights off the Nazi submarine U-853; a staunch building (the old San Francisco Mint built in 1874) stands firm on the city's darkest day.
s04e06 Idaho's Atomic Ghost Town 2025-07-10 03:00
Idaho's Atomic Ghost Town
The remains of Idaho's nuclear industry mark a new era of American history; a distillery in rural Kentucky revolutionizes liquor; a New England settlement prospers despite prejudice; subterranean chambers produce many of the nation's monuments.
s04e07 The Lair of the Mothman 2025-07-17 03:00
The Lair of the Mothman
A desert facility trains a nuclear strike force; a church becomes a sanctuary from racial violence; an old military building spawns a creature that haunts a small town.
s04e08 Secrets of the Olympia Brewery 2025-07-31 03:08
Secrets of the Olympia Brewery
A brewery in the Pacific Northwest sustains prospectors during the Gold Rush, a Wyoming mining settlement descends into lawlessness, and a brutal murder in a small Mississippi town sparks a revolution.
s04e09 America's Hidden Training Camp 2025-08-07 03:08
America's Hidden Training Camp
A military base trains soldiers in modern warfare to help defeat the Nazis, a suburban basement becomes a major cog in the Detroit bootlegging scene, and a brave woman leads a labor union against organized crime.