Built into an ice sheet in Greenland in 1959, Camp Century was described as a scientific research facility, but it was actually constructed as part of the top-secret Project Iceworm to test whether it was feasible to hide nuclear weapons under the ice.

In the 1940s and '50s, British hangman Albert Pierrepoint made a career out of executing everyone from infamous serial killers to Nazi war criminals.

While descending Everest after a successful summit, Hannelore Schmatz succumbed to the harsh conditions — and her frozen corpse remained on the side of the mountain for years afterward.

George Everest wasn't a mountaineer and never laid eyes on Mount Everest — so how did the world's highest mountain come to bear his name?

Over four nights in August 1990, Danny Rolling viciously murdered five college students in Gainesville, Florida — and after he was caught, police discovered these weren't his first killings.

No one could believe that mild-mannered Charlie Brandt had mutilated his wife and niece until they discovered his grisly past.

In 1980, Jean Hilliard froze near Lengby, Minnesota after spending six hours in the cold — but she was miraculously revived with minimal injuries the next day.

Made famous in the 1932 film Freaks, Schlitzie performed in most of the major circuses of the early 20th century after being sold into the business when he was just a child.

Known as the Candy Man and the Pied Piper, Dean Corll sexually assaulted and murdered at least 28 young men and boys in the Houston area between 1970 and 1973.

Anatoly Moskvin was considered an expert on local cemeteries in Nizhny Novgorod, Russia — but it turned out he was digging up deceased children and transforming them into "living dolls."