The ceramic pipes found at Pingliangtai, dating to around 2000 BCE, represent a sophisticated, coordinated urban project. This system wasn't for private bathrooms but for managing rainwater and wastewater across the entire walled settlement, showcasing centralized planning in a society without grandiose palaces or obvious ruling elites. For context, similar efforts appeared independently across the ancient world. In Mesopotamia around ~4000 BCE~, cities like Ur used clay sewer pipes for temples