The Great Pyramid of Giza is the oldest and largest of the three pyramids in the Giza pyramid complex and the only one of the Seven Wonders of the Ancient World to remain largely intact. Built as a tomb for the Fourth Dynasty Pharaoh Khufu, it took roughly 20 years to complete. It was constructed using approximately 2.3 million stone blocks, some weighing over 50 tons. For over 3,800 years, it was the tallest man-made structure in the world. The engineering precision is staggering; the sides are aligned almost exactly with the four cardinal points of the compass. Inside, it contains three main chambers: the King’s Chamber, the Queen’s Chamber, and an unfinished subterranean chamber. The pyramid represents the pinnacle of Old Kingdom architectural achievement and reflects the absolute power of the pharaoh and the Egyptian belief in the afterlife.