Mystery of Alexandria's largest coffin: Archaeologists unearth 8.6-foot-long stone sarcophagus buried in Egypt 2,000 years ago beside a massive stone head Experts say black granite sarcophagus found in Alexandria measures 8.6 ft long It was buried 5m deep during Ptolemaic period, which lasted from 332-30 BCE Archaeologists also found alabaster head, likely representing the tomb's owner Egyptian archaeologists have discovered what’s thought to be the largest granite sarcophagus ever found in Alexandria, measuring nearly nine feet long. The massive stone casket was buried more than 16 feet beneath the surface alongside a huge alabaster head – likely belonging to the man who owned the tomb. Experts say the ancient coffin has remained untouched since its burial thousands of years ago during the Ptolemaic period. Researchers working under the Supreme Council of Antiquities discovered the ancient tomb during an excavation in the Sidi Gaber district of Alexandria. The team was inspecting a resident’s land ahead of digs planned for the foundation of his building at Al-Karmili Street when they stumbled upon the remarkable Ptolemaic burial 5 meters deep. The Ptolemaic period lasted roughly 300 years, from 332-30 BCE, making this particular site more than 2,000 years old. According to the archaeologists who led the dig, the black granite sarcophagus stands at 185 centimeters tall (6 feet), 265cm long (8.6 ft), and 165 cm wide (5.4 ft). A layer of mortar identified between the lid and body of the stone coffin indicates it has not been opened since it was sealed off, says Dr. Ayman Ashmawy, Head of the Ancient Egyptian Antiquities Sector. Just who is buried inside, however – and the identity of the man in the alabaster carving – remains a mystery. .