For seven years, a Supreme Council of Antiquities team directed by the author surveyed and excavated the area in front of the First Pylon of Karnak Temple. The excavations revealed a great embankment at least 6.5 meters high, running roughly along the Nile’s north–south axis, indicating that the Karnak complex was built on a peninsula and had been surrounded by this huge embankment, which protected it from the erosion of the flood. The first phase in construction began during the late New Kingdom. Different extensions were subsequently added during the Twenty-fifth Dynasty and later. The area to the west of the embankment was used widely during the Greco-Roman period. There are houses, workshops, industrial activity buildings, and three bath complexes.