A Japanese bathhouse is a great leveller: it matters little that you speak no Japanese and that your fellow bathers speak no English.
And, of course, everyone is there just as God made us: naked.
Smiles, a courteous bow, and a demonstration of how to use the bathhouse equipment get you by. The Japanese find this ritual bathing not only cleansing but also of social importance. Skinship, you might call it.
Bathhouses are a cultural experience that can be very enjoyable for the tourist - especially after a hard day of sightseeing.
You're likely to encounter a bathhouse in your hotel. But tourists, ignorant of the proper bathhouse customs, ritual and etiquette, may feel intimidated on their first bathhouse experience.
I have to admit to nerves - and ignorance of the etiquette - on my first visit to a bathhouse (sento) or, more accurately, the more prestigious onsen (the hot springs version) in Oku-Hida, the hot springs region in the Japan Alps in the Chubu district of central Japan.
Oku-Hida spa village is surrounded by 3000m-high mountains. It boasts the largest number of open-air spas in Japan.
A feature of our mountain ryokan (hotel), the Hirayukan, is the indoor bathhouse.
In my room I find a yukata, a cotton unisex kimono, and a pair of slip-on sandals - many sizes too small for my oversize feet. (Fortunately, the maid had noted my 190cm frame and placed a yukata of an appropriate size in my room. But the sandals are another problem.)
So I shuffle down to the bathhouse, noting many other guests - men and women - in similar yukatas strolling through the building. It is an acceptable dress anywhere it seems but it does feel strange to be walking the public rooms in a bathrobe.
Also in my room are a small plastic bag and a towel the size of a face-washer. I'm not sure whether the tiny towel is for modesty or a more practical purpose.
I learn that, once disrobed in the bathhouse, one holds it in an appropriate place to discreetly cover vital parts and later, indeed, uses it as a washer.
Public bathhouses have existed in Japan for more than 400 years. The culture began in Buddhist temples in India and spread, via China, to Japan.
But the public bathhouse numbers are dwindling now as many more homes have baths or showers.
Like so many other things in 21st century Japan, modernity is killing old practices.
For some class-conscious Japanese, the bathhouse has become an embarrassing reminder of an impoverished past. Recreational bathhouses, like the one I'm visiting, have, however, kept the ritual alive.
They are civil and respectful places where privacy is respected. Contrary to western opinion, the bathhouse is not a sex palace. There are, however, a few bathhouses called Soapland where sexual needs are catered for. Many are strictly off-limits to westerners.
While the Japanese are usually very understanding if foreigners make cultural blunders, the public bath is one area where the uninitiated can seriously offend regular Japanese customers.
So, here I am at the doors of the bathhouse - on the one side, a blue curtain signalling the male bathhouse and a pinkish-red one on the other, for women.
Inside, one must follow a strict protocol. First I must remove my much-too-small sandals. That comes as a relief. They go into a shoe locker.
In the change room are shelves or baskets where one leaves his yukata and other belongings - even your room key. (Japanese wouldn't dream of pilfering anyone else's belongings.)
Oh, by the way, if you have tattoos you might be considered a member of the Japanese mafia - tattoos have been their traditional symbol. So, the stares might be for your tatts rather than anything else.
The bathhouse is roughly divided into two parts: one where you wash and relax, the other the hot baths.
Before entering the hot baths it is vital that you scrub every part of your body. You scrub as if a surgeon preparing for an operation. The hot water of the public bath is meant for soaking, not cleaning.
That's when I discover the value of the piece of cloth I have been given. By now I'm in the buff and I sit on a midget stool in front of a mirror and table which holds liquid soap, shampoo, pumice stone, shower caps and other goodies - including a razor should I need a shave. (A toothbrush is also provided should I need to scrub the fangs.)
A flexible shower head enables me to reach every part of my body. Most baths are classed by temperature, tepid or warm. But because I can't read Japanese I have to dip my toe in.
The "warm" is actually hot - 40C, or thereabouts. In fact, the water bubbling out of the ground is so hot it has to be cooled before it goes into the bathhouse.
Outside, an early snowfall is dusting the landscape white. But inside in the bathhouse steam is rising off the plunge pool.
Suitably cleaned, I sit on the edge of the pool. Soaking next to me is a man whose only conversation comprises loud "Arrrrgh" - sounds of contentment, I think. And so the next 10 minutes passes in gorgeous relaxation.
Usually there is also a cold water plunge pool nearby. Be brave and dip in.
Afterwards, in the change room, I find amenities such as powder, skin moisturisers, hairbrushes and toothbrushes. Some also have massage chairs. Cold drinks are also available. You might want to ignore the bathroom scales there.
Open-air hot springs abound in this region so you can enjoy a bath, al fresco, while you watch the steam rise into the cold mountain air.
In the background are the snow-capped Japan Alps.
Hot springs usually contain minerals and you'll find resorts where guests will stay a week or so for health reasons. Hotel bathhouses are usually open until midnight.
Oh, what a great feeling to set myself up for a good night's sleep.
As we leave the ryokan next morning, my bath buddies give me a cheery wave goodbye. It appears I've passed my bathhouse test.
- The writer was a guest of the Japan National Tourism Organisation.