The Great Pyramid of Giza (also known as the Pyramid of Khufu or the Pyramid of Cheops) is the oldest and largest of the three pyramids in the Giza pyramid complex bordering what is now El Giza, Egypt. It is the oldest of the Seven Wonders of the Ancient World, and the only one to remain largely intact. Based on a mark in an interior chamber naming the work gang and a reference to fourth dynasty Egyptian Pharaoh Khufu, Egyptologists believe that the pyramid was built as a tomb over a 10 to 20-year period concluding around 2560 BC.
On the Giza Plateau, Khufu's builders oriented his pyramid almost perfectly north. The largest pyramid ever built, it incorporates about 2.3 million stone blocks, weighing an average of 2.5 to 15 tons each. It is estimated that the workers would have had to set a block every two and a half minutes.
The pyramid has three burial chambers. The first is underground, carved into bedrock. The second, aboveground chamber was called the queen's chamber by early explorers. We now know it was never intended to house one of Khufu's wives but perhaps a sacred statue of the king himself. The third is the king's chamber, which held a red granite sarcophagus placed almost exactly at the center of the pyramid. The king's chamber is accessed via the 26-foot-high (8-meter-high) Grand Gallery, which was sealed off from thieves by sliding granite blocking systems.
The Great Pyramid was the centerpiece of an elaborate complex, which included several small pyramids, five boat pits, a mortuary temple, a causeway, a valley temple, and many flat-roofed tombs for officials and some members of the royal family.