Ancient abandoned locations usually feature a troubling tale to explain why they became deserted, but in modern times such sites are often shrouded in mystery.
YouTube user Dark5 has put together a showcase of five places around the world and the puzzling circumstances by which they were forsaken.
Perhaps the most puzzling site featured in the list is a massive skyscraper in North Korea known as the Ryugyong Hotel.
Standing 105 stories tall and featuring a whopping 3,000 guest rooms, the giant structure cost an astounding $750 million dollars to build over the course of three decades.
And yet, for reasons no one can explain, the 'Hotel of Doom' has never been used.
Once envisioned as a towering message about North Korean might, the nation's notoriously secretive government has even taken to airbrushing it out of officially sanctioned photos of the Pyongyang skyline.
Another relatively obscure site on the list is the remains of a bunker that was built for Hitler in the 1930's that resides in the Hollywood Hills!
Construction of the 'Fuhrer bunker,' dubbed the Murphy Ranch, was never completed as plans for Hitler to come to America were abandoned after the Pearl Harbor attack prompted US officials to raid the site.
A look at the blueprints for the site reveal a bizarre layout which featured an elaborate fountain that showcased the twelve signs of the Zodiac.
Despite being left to ruin almost 75 years ago, the structure still remains in the outskirts of Los Angeles and is often visited by curious explorers who have heard the tale of the lost Nazi camp in Hollywood.
Other odd locations detailed in the video include a 'space gun' that was abandoned by the United States in Barbados in 1967 and a breathtaking HAARP-like base in the Ukraine that the Soviet Union abandoned following the Chernobyl disaster.
Check out the complete video to learn more about these remarkable modern ruins and perhaps find a unique place for your next adventurous vacation.