A Roman board game has mystified researchers for years. AI discovered how to play

Somewhere around the turn of the 20th century, archaeologists in Heerlen, Netherlands, came across an odd-looking smooth white stone. They knew the territory was once the Roman settlement of Coriovallum, but had never seen anything like it and had no idea what it was for.

For the better part of the next 100 years, the stone sat in a storage unit at the Thermenmuseum (Thermal Bath Museum), a mystery taunting researchers. Then, six years ago, archaeologist Walter Crist spotted it while wandering the museum.