Being a history researcher means endless hours of poring over books, paintings, photos, and manuscripts, looking for clues from the past to create an accurate picture of what things were really like.

Naturally, when following a lead it can be easy to be led down all kind of interesting ‘rabbit holes,’ and that’s precisely what happened to author and Ph.D. student Paul Cooper, from Norwich, England, while researching the Temple of Olympian Zeus, the ruler of gods in Greek mythology, in Athens, Greece.

Paul came across an incredible photo of the Zeus temple’s ruin, taken way back in 1858. “I was researching the forgotten histories of different ruined sites around the world for my Ph.D., which looks at how our attitudes and artistic representations of Greek architecture ruins has changed over history,” Paul told Bored Panda. “As a novelist and a writer of historical fiction, ruins are important in my work.”

This particular photo intrigued him, as there was something weird perched atop the temple pillars. What on earth could it be? The strange little hut-like appendage is nowhere to be found on the Temple of Zeus ruins as they stand today. It was also absent on an identical photo that he had unearthed after further research.

Digging deeper, he found a painting of the Greek temple ruins and more photos from a similar period. The little stone hut was there, sitting proudly atop the great temple again! The intrigue intensified, and so did Paul’s curiosity. Could there have been people living up there, perched precariously on top of one of ancient history’s magnificent temples? Why was the hut included in some photos, but not others? And why isn’t it there anymore?

Paul loves exploring the stories behind the many ancient ruins scattered across the world, from North Africa to Cambodia and beyond. He spent time exploring the incredible ruins of Polonnaruwa in Sri Lanka whilst writing his first novel ‘River of Ink.’ “Many ruined sites have hidden or erased histories that take place after the building has been ruined,” he told us. “For instance, the ruins of the Acropolis in Athens were once the site of an Ottoman mosque, and the Colosseum held a Christian heritage. The ruins of Palmyra in Syria were once home to a thriving town before it was demolished by French archaeologists in the 1920s.”

So what hidden secrets does the Temple of Olympian Zeus hold? Scroll down below to find out for yourself, as Paul uncovers the mystery in a viral Twitter thread. Let us know what you think about it in the comments!