The Great Pyramids consist of the Great Pyramid of Giza (known as the Great Pyramid and the Pyramid of Cheops or Khufu), the somewhat smaller Pyramid of Khafre (or Chephren) a few hundred meters to the south-west, and the relatively modest-sized Pyramid of Menkaure (or Mykerinos) a few hundred meters further south-west. The Great Sphinx lies on the east side of the complex, facing east. Current consensus among Egyptologists is that the head of the Great Sphinx is that of Khafre. Along with these major monuments are a number of smaller satellite edifices, known as "queens" pyramids, causeways and valley pyramids. Also associated with these royal monuments are what appear to be the tombs of high officials and much later burials and monuments (from the New Kingdom onwards).Of the four major monuments, only Menkaure's Pyramid is seen today without any of its original polished limestone casing. Khafre's Pyramid retains a prominent display of casing stones at its apex, while Khufu's Pyramid maintains a more limited collection at its base. Khafre's Pyramid appears larger than the adjacent Khufu Pyramid by virtue of its more elevated location, and the steeper angle of inclination of its construction ? it is, in fact, smaller in both height and volume. The most active phase of construction here was in the 23rd century BC. It was popularised in Hellenistic times when the Great Pyramid was listed by Antipater of Sidon as one of the Seven Wonders of the World. Today it is the only one of the ancient Wonders still in existence.