Juan Carlos Montes/Panoramio
Amongst the small houses on a hill in Caracas, Venezuela, the massive Helicoide looks otherworldly - or at the very least, out of place.The spaceship-like building was originally planned as a drive-through mall. Instead of walking, shoppers would have been able to drive right into the complex and park in front of the shops they wanted to visit. (Though, the shops wouldn't have drive-through windows.)
Construction on the mall started in 1956, but the project was abandoned a few years later because of funding woes.
Over the next few decades, the building transformed into a prison and, according to several former inmates, a torture chamber for political prisoners.
A new book by historians Celeste Olalquiaga and Lisa Blackmore, "Downward Spiral: El Helicoide's Descent from Mall to Prison," aims to bring its mysterious history to light.
Take a look below.