Humans have always been obsessed with preserving images of daily life. But with the advent of modern photography in the 1800s, we have been able to capture and preserve more than what is necessary. Over the decades since the invention of modern cameras, mysterious occurrences have been captured in hundreds of photographs that even with today’s technology are hard to explain. Keep in mind that there were no digital imaging and editing technologies when photography was still in its infancy. And altering images back then was a painstaking process. Which is why photographs of ghostly images, “monsters,” and other bizarre events from those era have baffled even the experts in the field of photography.

What follows are 33 of the world’s most spine-chilling and mysterious photographs that are yet to be explained.

The hanging body in the Cooper family photo

When the Cooper family moved to their new home in Texas in the 1950s, they suspected nothing unusual about the place. But when they took a family photo, the developed image included what looked like a ghostly image of a body hanging upside-down from the ceiling. Many theories were brought up to explain, one of which was that it was an apparition of one of the previous occupants of the house.