A Polish castle becomes entwined in the hunt for lost Nazi treasure, the heir of an American business tycoon gets caught in a web of controversy and an Irish estate is embroiled in a fight for freedom.

A place of hope in the Czech Republic quietly perseveres in the age of Nazi tyranny, a Moroccan politician sides with the French and an eco-friendly paradise in the Amazon proves to be unsustainable.

In modern-day Turkey, on the coast of the Aegean Sea, archaeologists discovered hilltop ruins that are believed to be the site of one of the world's most enduring stories.

An eerie prison with a dark past that became the setting of an iconic Hollywood movie and alien monoliths on a strange and remote island are deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

A majestic estate for the rich and powerful now lies abandoned in the highlands of Argentina; experts investigate and uncover a once struggling hotel that was transformed into a luxurious resort outpost for elite Nazi German sympathizers.

This spooky, unfinished amusement park serves a different purpose nowadays.

Exploring what happened to the large town just outside of Chernobyl on the eve of disaster, a fleet of ghost ships, and a dangerous mountain road that changed history.

Some of the world's most incredible engineering projects are now deserted; Explore what happened to a cutting-edge research complex built by a visionary genius, an ambitious Nazi project that met a sinister end, and a Cold War relic that changed history.

A mysterious American pyramid built out of Cold War paranoia, a haunted prison, and a cluster of structures in the Atlantic are mysterious deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

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 reveal how they were built and why they were abandoned.

A terrifying sea fortress, a highway in the Amazon that suddenly vanishes, a mysterious structure in the shadow of the Statue of Liberty are deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

In a California desert, a once glittering Hollywood hotspot gets converted into a top-secret interrogation center for POWs.

Abandoned engineering projects include a classified Soviet machine built to prevent all-out nuclear war, a top-secret Nazi facility, and a strange tower that left an enduring legacy.

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.

An American ghost town in the Amazon jungle, a secret Nazi base, and a deadly concrete fortress 866 miles long are mysterious deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

A porn baron dreams up a hedonistic paradise to avert nuclear catastrophe.

Half-built castles stand as a whimsical reminder of a neighborhood that was supposed to feature thermal baths and panoramic views; the ambitious project came to an abrupt halt when the construction company began to face financial difficulties...

The series about abandoned engineering achievements begins with a Soviet megastructure, massive Nazi brainwashing complex and dangerous desert pass.

The ruins of a coastal fortress sit atop a jagged outcrop along the beaches of Wales; experts investigate and uncover a derelict 19th-century British fortification that housed a series of occupants, including an exotic, private zoo.

Graffiti scratched into the walls of a military base on the British coast sheds light on a secret raid against the Nazis.

Exploring a ghost town that was once a dangerous industrial hellscape, a giant warship at the bottom of the ocean, and a top-secret relic that could have changed the Cold War.

Stories of incredible engineering projects that are now deserted, including a massive military site that was once a hotbed for nuclear testing, a top-secret airbase hidden inside a mountain, and an otherworldly power plant.

A strange Cuban prison, an eerie escape route built for Armageddon, and an underwater marvel that changed history are mysterious deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

An alien Nazi structure that changed history, a strange Soviet monolith known as the Tower of Death, and a concrete ocean giant are deserted engineering projects, and new discoveries reveal how they were built and why they were abandoned.

A deserted town in Spain with a bloody past and a ghost fleet heading nowhere are homes to dark American secrets, and new discoveries reveal how they were built and why they were abandoned.