The ancient civilization known for its pyramids along the Nile is Ancient Egypt. This civilization flourished from around 3100 BC until the conquest by Alexander the Great in 332 BC. The pyramids served as tombs for pharaohs and are a testament to the advanced knowledge of architecture and engineering that Egyptians possessed. Sites like the Pyramids of Giza and the Sphinx reflect the cultural and spiritual beliefs of the time, showcasing their devotion to the afterlife.