The Serapeum was the sanctuary dedicated to Serapis, the head of the Alexandrian divine triad during the Graeco – Roman period ( 306 BCE – 325 CE ). In later periods, the Serapeum became know as Amoud el – Sawary and also as Pompey’s Pillar, due to a mistaken identification of Diocletian’s Column, which dominated the site. Serapis was a syncretic deity created by the Ptolemies, with traits of the Egyptian gods Osiris and Apis, and a physical appearance similar to the Greek gods. Appealing to both Egyptians and Greeks, Serapis become one of the most important Alexandrian cults. Such a popular cult needed a central temple to welcome pilgrims. The sanctuary was situated on a hill in Rhakotis, the oldest and largest neighborhood of the city, which was populated by Egyptians. The earliest evidence from the temple complex dates from the reign of Ptolemy II, while the main temple structure dates from the reign of Ptolemy III, and a temple dedicated to Harpocrates was built under Ptolemy IV. The foundation plaques of the temple, made of gold, silver, clay and glass, were bilingual, written both in Greek and hieroglyphs. The principle Ptolemaic temple was burnt down in 181 CE and rebuilt again larger than before during the Roman period. In 391 CE, when Christianity had become the official state religion of the Roman Empire, the Serapeum was finally closed and destroyed in the conflict between the Christians and the pagans. Then, a church dedicated to St. John the Baptist and Elisha was built on the site. Later, during the Arab and Ottoman periods, building material from the abandoned structures of the Serapeum was dismantled and reused elsewhere in the city , while in 1167 CE, Saladin had some of the columns dismantled and thrown into the harbor of Alexandria to defend it from the Crusader ships. Pompey’s Pillar The site is marked by a massive red granite monolith, mistakenly called Pompey’s Pillar by medieval travelers. The column was dedicated in 298 CE to Emperor Diocletian, who saved the besieged city from famine by suppressing an Egyptian uprising. The column with its base and Corinthian capital is 27 m high with a shaft of 9 m in diameter. The Underground Galleries The underground galleries are part of the earliest phase of the Ptolemaic complex. Their purpose remains uncertain; for years, they were mistakenly identified as part of the Library of the Serapeum, once considered the daughter of the great Library of Alexandria. However, they appear to be underground galleries with niches for the burial of sacred animals, like those of Serapeum in Memphis. Two red grantie Ptolemaic sphinxes found in situ in 1906 ( most likely from the reign of Ptolemy VI, 180 – 145 BCE ) sit perched beneath Pompey’s Pillar as well as a statue of Isis which was recovered from the sea near the fort of Qaitbay. The site also retains several Pharaonic relics, or Pharaonica, such as a giant scarab, and a statue of Ramses II, which was transported to the hill from Heliopolis in Memphis near modern Cairo. To visit the Serapeum today is to gain a unique glimpse of a spiritual tradition which once spanned centuries and united continents and cultures. The Nilometer To the east of Pompey’s Pillar there was a Nilometer : a typical fixture of Egyptian temples for measuring water levels during the annual flooding of the Nile. The Basalt Statue of the Apis Bull (replica) A statue of Serapis in his incarnation as the Apis bull with sun – disk between his horns was found at the end of the subterranean galleries. Its podium bears a dedicatory inscription by Hadrian . The original was moved to the Graeco – Roman Museum of Alexandria.