In 1500 B.C., the people of Crete invented sewage disposal systems. Evidence also indicates that the ancient palace of Knossos had a water closet with a wooden seat and flushing system.
In 500 B.C., the Roman Empire had a system of aqueducts and pipes that created indoor plumbing for bathhouses and public wells, which greatly helped with sanitary conditions. In 1596, Sir John Harrington invented the first flushing water closet, but the invention failed to stick due to poor advancements in sewage systems. In the 17th century, French castles were outfitted with indoor privies. However, they emptied into surrounding moats until a sewage system was designed.
In the 18th century, sewage systems, piping and drains were expertly designed and installed in Chicago and New York City. From 1900 to 1932, water closet designs had several hundred pending patents. Charles Neff and Robert Frame designed the plumbing system that has become the standard in the United States.