There are between 81 and 112 pyramids located throughout Egypt. Most pyramids are found in northern or southern Egypt, and it took an average of 27 years to construct each pyramid. The largest and oldest pyramid is the Great Pyramid of Giza, built for Pharaoh Khufu around 2560 BC. It is the only surviving structure of the Seven Wonders of the Ancient World. Other notable pyramids include the mostly ruined pyramid of Djedefre at Abu Rawash, the earliest step pyramid at Saqqara built under Djozer, and the pyramids at Dahshur including the Black Pyramid built for Amenemhet III.