Sentō

Sento are Japanese public bathhouses. People take baths together there. Many Japanese people think of sento as an important part of Japanese culture, with its manners and ideas about communities.
Sento are not the same as onsen. Onsen are baths built on natural hot springs. Onsen water has dissolved rock in it. Sento water is either tap water or well water. Some sento may add good-smelling plants or bath salts to the water. Sento cost less than onsen to visit.
Today, sento are not as popular as they once were. This is because people have bathtubs and showers in their homes. They do not need to go to a sento to clean. Many people still go to sento, but they go to enjoy the water and relax. The Tokyo Sento Association makes sure going to a sento does not become expensive because they want people to be able to go to sento. Local organizations decide the price. For example, in Tokyo, the Tokyo Sento Association decides the price. In 2020, the price to go to a sento in Tokyo was Y=480, or a little over US$4.10.
Architecture
On the outside, some sento look like temples. The entrance has a Japanese curtain called a noren. Noren at sento are usually blue. Most sento have concrete or steel chimneys for the boilers that heat the water. Sometimes, a person can find a neighborhood's sento by looking for a building with this kind of special chimney.
The dressing area is usually made in the traditional Japanese style, with wood and dark colors. The bathing area are usually made with tiles and is full of light. Japanese people think of this style as Western.
Sento have separate places for men and women, but young children can go to either side. Babies often go with the women. Fathers take boys and very young girls to the men's side. Sometimes there is a door between the men's and women's sides. Children are allowed to go through the door.
Many sento have a large mural, or wall painting, near the tubs. Many are landscapes or pictures of Mount Fuji. The water in the air is bad for the paint, so the murals wear out. Repainting a mural in the one day a week that a sento is closed is hard to do, so some sento use tiled mosaics or a window that looks out on a garden for decoration instead.
Some sento owners and their families live in rooms at the back of the building.
History
People built the first sento during the Nara period, in the 700s. The first people to use sento were monks. They used the sento for ritual purification. Later, more sento were built for ordinary people to go and get clean. By 1700, most of the neighborhoods in Tokyo, then called Edo, had their own bathhouse. Many of the sento of that time were steam baths, not soaking baths. They did not have windows, so the bathers could not see very well. Sometimes the water was dark and dirty.
In 1868, the Meiji Restoration took away some of the class system of Japan. After that, many former nobles or samurai took baths with the regular people in sento.
Tsurusawa Monzaemon had the idea for modern sento in 1878. Instead of a steam bath, he built a big tub that the bather could sit down in. He put windows in his sento so there would be light to see by. This made it easier to see whether the water was clean. People liked these new sento and soon built many more of them. In 1885, the government said no one could build the old, dark sento any more. All new sento had to be light so they could be kept clean. They also passed a law against men and women bathing together, but no one cared about it until after many foreigners began to visit Japan later in the Meiji period (late 1800s).
In the 20th century, sento became less popular. To keep customers, sento owners put in bubblers, exercise equipment, saunas, electric shocks and other things bathers could not get at home. In 1972, there were about 21,200 sento in Japan. This went down to 13,250 in 1985. There were 499 sento in Tokyo as of 2021.
Super sento
People began building super sento in the second half of the 20th century. Super sento have more things to do than regular sento. Some have water slides, swimming pools, or restaurants. Super sento are meant to be fun instead of relaxing.
Manners
Before entering, visitors take off their shoes and put them in shoe lockers. At sento in Japan today, it is not good manners to clean one's body in the bathtub. Bathers must shower before getting in the water. This keeps dirt, sweat and other things from making the water dirty. Many sento provide soap and towels. Bathers sit on a stool in the shower. The bathers must not wear any clothes or swimsuits in the sento. Bathers may use towels at the sento or bring their own, but the towel must not go in the water. Bathers put the towels on their heads instead. People with long hair tie it up so it does not get in the water.