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.

Remains of a grand vision become a symbol of excess in the Turkish capital.

An underground labyrinth can warp the mind and turn friend into foe.

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 fantasy land lies in the heart of Alabama, a place of refuge in Ireland becomes a house of horrors, a South Korean city is scarred by a violent crackdown and traces of a brutal industry remain along the arid Namibian coast.

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.

Desert bunkers in Tunisia block Allied victory in Africa; the pride of one Alabama community is born out of a harsh reality; a Lebanese complex is rocked by a massive explosion; the remains of an elite institution still stand in Greece.

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.

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.

The world's strangest ghost towns are home to dark secrets, creepy buildings and eerie sights; new discoveries reveal why they were abandoned.

A slice of the Miami suburbs stands out for its style and history; a hotel in Lebanon carries the scars of a civil war; a pirate radio station gets a mixed reception.

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.

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.

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 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.

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.

A stronghold in Panama defends a prized American possession, a mad scientist shares an herbal remedy from his hilltop castle, a ghostly German railroad divides a fractured city and a Bulgarian mountain retreat offers hope to its residents

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

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.

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.

In Alaska, the ruins of a massive compound point to eerie evidence of an apocalyptic mystery. New discoveries reveal why this strange marvel was built in the snowy wilds of the Last Frontier and why it was abandoned.

An abandoned system of caves was once the meeting place of a secret society that worshiped Satan and performed black magic, and new discoveries at this mysterious site reveal what really happened here and why a Founding Father was a frequent guest.

An abandoned theme park is home to secrets of a forgotten, imaginary world.