An international team of archeologists have discovered a massive tomb that belonged to one of ancient Egypt ’s earliest pharaohs. However, the ruler’s identity remains a mystery—as do many details of his long-lost dynasty.

The burial chamber most likely belonged to a ruler in a line of kings once lost to history, researchers said. “It’s a new chapter in investigating this dynasty,” one noted.

Archaeologists date tomb, apparently stripped bare by ancient grave robbers, to chaotic Second Intermediate Period, when Egypt was divided into at least 4 kingdoms