Sewage system, ca. 2600 BC
The earliest sewage facilities belonged to the Indus Valley civilization: in Mohenjo-daro, there were public toilets and a city sewer system. Sewage was also known in Ancient Babylon, some Chinese cities, and in Rome, where it was represented by a colossal engineering project called Cloaca Maxima ("Greatest Sewer") that survives to this day.