A MUST! The Onsen (Public baths)
The Onsen is a Japanese tradition which is an absolute must for a visitor who wants to get a glimpse of day to day Japanese life. The Onsen (public baths) facilities vary a lot from place to place, but they have similar customs across the board, plus they remain very popular with the Japanese. It isn't uncommon for them to visit the baths several times per week to talk, socialize and mingle. No experience in Japan can quite compare to a visit to the Onsen.
The public baths are similar to what we used to have in the west, only as more and more people have added running water to their homes in Japan, instead of going out of business, they went upscale. Instead of paying five cents and getting a towel, you pay Y1000 ($10) and get a towel, a toothbrush, perfume/cologne and unlimited access to spa quality facilities kept
immaculately clean.
The baths all have pools of several different kinds of hot water, as well as hot tubs, saunas, and bathroom style sinks. Some are indoor and some are outdoor, and in winter, the outdoor ones are simply one of the most stimulating things I have everexperienced. In addition to these facilities, each baths has its own special features. The best one I tried was a set of three nozzles set four meters above the ground that were shaped so as to gravity drop a firehose thick rope of clear hot water. Putting your clavicle under one was like getting the best shiatsu massage that ever existed.
The public baths require full nudity but are segregated by sex. Non-Japanese are somewhat rare, especially in the rural areas, and you can expect to be stared at if you go. Small children of the opposite sex may accompany either parent. Tattoos need to be covered. Conversation is quiet. Most baths have adjacent facilities to purchase food and drink at reasonable prices. Elaborate baths offer pajama style clothing and more extensive facilities such as green tea baths and places to watch television. Most if not all also offer open floor massages during set times and for set prices.

Another great view, best with beer
The raccoon figure denotes pleasure
Iya On-Sen
Whirlpools forming off the bow