The third millennium B.C. was the "Age of Cleanliness." Toilets and sewers were invented in several parts of the world, and Mohenjo-Daro circa 2800 B.C. had some of the most advanced, with lavatories built into the outer walls of houses. These were "Western-style" toilets made from bricks with wooden seats on top. They had vertical chutes, through which waste fell into street drains or cesspits. Sir Mortimer Wheeler, the director general of archaeology in India from 1944 to 1948, wrote, "The high quality of the sanitary arrangements could well be envied in many parts of the world today."
In fact throughout the 16th, 17th, and 18th centuries, the use of public baths declined gradually in the west, and private spaces were favoured, thus laying the foundations for the bathroom, as it was to become, in the 20th century. However in Japan shared bathing in sento and onsen (spas) still exists; the latter being very popular.
