A travel article by Susan Pigg that looks at the Nile cruise experience, and breaks the main sites down into digestible chunks (and is more useful than the usual travelogue): "Aswan was the source of much of the granite used for the Pyramids of Giza and the massive obelisks erected to mark temple entrances. The stone was chipped out of the ground (without benefit of metal tools), loaded on boats and floated down the Nile. You begin to understand the super-human effort involved when you visit the quarry of the Unfinished Obelisk not far from the waterfront. Ancient Egyptians had chipped three of the four sides of a 42-metre pillar (it would have been the biggest in Egypt) out of the bedrock before discovering a crack so big, they abandoned it."
See the above page for the full piece.