Dr. David Silverman, Curator-in-Charge, Penn Museum, Egyptian Section, presents the opening lecture in the Great Wonders Lecture Series. The most recognized of the Seven Wonders of the Ancient World, Giza's pyramids and Sphinx have fascinated humankind for more than 5,500 years. At 240 feet long and almost 70 feet high, the Sphinx is Egypt's largest statue; at a height of 481 feet, the Great Pyramid was the world's tallest built structure for several thousand years. Many questions, debates, and theories focus on their purpose, age, origin, and creators. Did indigenous peoples, slaves, or ancient aliens build them? Did secret chambers lie within? Could pyramids magically preserve their contents? Did the elements in the solar system guide their placement on the Giza plateau?