Which ancient civilization built the PYRAMIDS at GIZA?

The Pyramids at Giza (on the outskirts of modern Cairo) were built by ancient Egyptian civilization. The Great Pyramid of Khufu (~2560 BCE) was originally about 147 meters tall (now ~139 m after erosion of outer casing stones) and remained the world's tallest human-made structure for nearly 4,000 years until surpassed by Lincoln Cathedral's spire ~1300 CE. The two smaller pyramids at Giza were built for Khafre and Menkaure, Khufu's Fourth Dynasty successors. Egyptian pyramid-building peaked during the Old Kingdom (~2686–2181 BCE) as royal tomb architecture.