Onsen

An onsen (温泉) is a hot spring in Japan. Japan is volcanically active and has thousands of hot springs across the entire country. The term onsen also refers to the baths, the inns, and the areas surrounding the springs. Onsen are in important part of Japanese culture and tourism. Onsen play an important role in 'naked communion' (裸の付き合い hadaka no tsukiai), in which people can move past walls of work and life and truly get to know their fellow bathers. As such, work trips often involve visiting onsen.

Onsen are typicially marked on maps using the ♨ symbol or with the kanji 湯 (yu, meaning hot water). Other times, onsen are designated with the hiragana ゆ (yu).

Types of Onsen
There are many different styles and types of onsen. There are outdoor onsen (露天風呂 or 野天風呂 roten-buro or noten-buro), indoor onsen, and onsen theme parks, and resorts. Onsen should not to be confused with sento (銭湯), public bath houses using regular water. Indoor

Etiquette

 * Clean yourself up!  After stripping down to your birthday suit in the changing area, you head off into the onsen. There are bathing stations in the onsen with stools, taps, buckets, and often times soap and shampoo. At both onsen and sento alike, you are expected to thoroughly bathe and rinse yourself prior to entering the water. It is a taboo to enter the bath while still dirty or soapy.
 * Towels. You normally have two towels when you use the onsen. One is your regularly sized bath towel, and one is a smaller 'modesty' towel. The regular sized towel should stay behind with your clothing while you bring the normal towel in with you. The smaller towel can be used as a wash cloth in the bathing area but not in the onsen itself. You are generally discouraged from placing your towel in the onsen water. When bathing, you can either place the towel to the side or place it on the top of your head.
 * Hair. It is genrally considered rude to completely submerge in the onsen. If you have longer hair, it is also considered rude to have your hair trailing in the water and you are encouraged to tie it up.