Scattered around the world are long-forgotten engineering marvels, decaying cities and empty factories that once stood on the cutting edge of design and construction. Today they are discarded, dangerous, and some of them are even deadly. Mysteries of the Abandoned reveals why these engineering triumphs were built and how they were left to crumble. In each hour long episode, stories tell of who originally designed the structure, its historical significance, and why it was ultimately no longer viable. California's Goat Canyon Trestle railway, Pennsylvania's Kinzua Viaduct steel bridge, the Grand Goulets Road in the French Alps, and Hashima Island, a once thriving and now deserted Japanese island, are among episode subjects.

For the past seven years, engineer Philip Grossman's obsession has been the abandoned landscape that has developed out of the infamous nuclear disaster at Chernobyl. In 2015, he and his wife even got married there. Traveling there ten times, he is one of only a few people that have been allowed nearly unrestricted access to the highly dangerous exclusion zone, the area immediately surrounding the site of the 1986 nuclear reactor explosion. Pursuing leads that hint at possible CIA espionage and an internal Soviet cover up, Grossman hopes his latest trip will be the one where he finds the clues to what may have caused the largest nuclear accident in history.

Traces of a Russian hole to hell in the Arctic, a military base in America's wild west, and a strange looming tower are mysterious deserted engineering projects, and new discoveries real how they were built and why they were abandoned.

A secret Russian military base in the Gobi Desert, a strange complex in an American wasteland, and a relic high atop a mountain are mysterious deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

A secret structure on a sinister mountain, an industrial compound swallowed by a forest, and a mysterious run in a sand dune are strange deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

Scattered around the world are long-forgotten engineering marvels, decaying cities and empty factories that once stood on the cutting edge of design and construction. Today they are discarded, dangerous, and some of them are even deadly. Mysteries of the Abandoned reveals why these engineering triumphs were built and how they were left to crumble. In each hour long episode, stories tell of who originally designed the structure, its historical significance, and why it was ultimately no longer viable. California's Goat Canyon Trestle railway, Pennsylvania's Kinzua Viaduct steel bridge, the Grand Goulets Road in the French Alps, and Hashima Island, a once thriving and now deserted Japanese island, are among episode subjects.

A strange alien shrine on a mountain peak, a bridge built in the Alaskan wilderness, and an American castle with a dangerous secret are mysterious deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.