The major construction project completed in Egypt during the reign of Pharaoh Khufu was the Great Pyramid of Giza, around 2580-2560 BC. This monumental structure served as a tomb for Khufu (also known as Cheops) and is a testament to the engineering skills of ancient Egyptians. The pyramid was originally 146.6 meters tall, making it the tallest man-made structure for over 3,800 years. Its construction involved thousands of workers and intricate planning, showcasing the centralized power of the pharaoh and the state. The Great Pyramid is one of the Seven Wonders of the Ancient World, symbolizing ancient Egyptian achievements.