On 15 December 1877 Baden-Baden opened a new bath house on the slope of the Florentinerberg, over the ruins of the baths the Romans had built there. The town had reason to hurry. A law of the North German Confederation had banned gambling, and the casino that paid for Baden-Baden's reputation was about to stop paying. So the district building inspector Carl Dernfeld and the doctor Carl Frech were sent to look at the best-known baths of the day, and what they brought back became the Friedrichsbad, a Renaissance-style building that, its operator says, was described at its opening as the most modern bath house in Europe.
They still undress for it. On five days of the week — Monday, Tuesday, Thursday, Friday and Sunday — the Friedrichsbad is, in the operator's words, bathed "traditionally without swimwear". Men and women bathe together; the operator says it went that way because of strong demand for shared bathing days. The remaining two days are swimwear days, and on those, swimwear is the only option.
That arrangement, a building with a clear rule and a clear exception, is the whole subject in miniature. Textile-free bathing is not a secret and not a subculture. It is a house rule, posted like any other, and the hard part for a visitor from somewhere else is only that nobody at home warned them.
Why do German saunas ask you to take your swimsuit off?
The short answer is custom, and the German Wikipedia article on the sauna puts it plainly: in the German-speaking countries and in several northern European ones, saunas are as a rule entered naked, the exception being what Germans call a Textilsauna. In much of the Romance-speaking world the reverse holds, and naked sauna-going is unusual or even forbidden. In the United States and parts of Asia the swimsuit sauna is the normal kind.
The longer answer is the set of reasons people on the textile-free side give, and Wikipedia lists them without taking sides. Tradition comes first. Then hygiene and physiology: a swimsuit gets in the way of the heat moving over your skin, and sweat stays where the fabric holds it. Then chlorine, carried into a hot wooden cabin in a costume that was in the pool ten minutes ago. The same article is fair to the other camp, whose arguments are discomfort at enforced nudity and, with a certain irony, the poor heat circulation that comes from towels wrapped round tightly out of embarrassment. Among German sauna-goers, it adds, the question is often argued with some emotion.
The movement behind the wider custom is older than most of the baths. German naturism, Freikörperkultur or FKK, grew out of the life-reform movement around 1900. The writer Heinrich Pudor coined the word Nacktkultur in 1902; in 1926 Adolf Koch opened a school of physical culture in Berlin where men and women exercised together undressed, as part of a programme of what he called physical hygiene. The English Wikipedia article on the subject notes that the movement was careful to take the erotic out of the nude body. That is still the tone of a German sauna: practical, quiet, slightly bored.
None of that means every bath in the region is textile-free. A ticket to a German Therme often covers two worlds under one roof, a pool hall where you wear a swimsuit and a sauna area where you do not. The count of baths that state the opposite, swimwear required throughout, is 3. More often the rule belongs to a room, and sometimes only to an hour.
What do the house rules actually say?
Read three or four of them and a pattern appears. They are short, they are specific, and they are much less dramatic than the anxiety they cause.
Katara, at Belsele between Ghent and Antwerp, is the most direct. Its sauna rules open with the sentence that settles the matter: Katara is a naked sauna. On Wednesday, the house's swimwear day, a bathing costume is required, and the operator specifies what counts — short swim briefs for men, a bikini or a swimsuit for women. On every other day you go through the baths naked and swimwear is not allowed. Whatever the day, you wear a bathrobe when walking between rooms. In the cabins your body lies or sits entirely on a towel, and the rule says "also your feet". Phones, tablets, smartwatches and smart glasses stay in the locker, and cameras are strictly forbidden. Asked why the place is undressed, the operator's answer is not about health at all: discreet nudity and respect for one another come first.
The Netherlands and Flanders share that outlook. Wikipedia describes mixed-sex nudity as the generally accepted rule in Dutch saunas, with some offering women-only or bathing-suit-only times for guests who would rather not.
The Kristall Wohlfühltherme Ludwigsfelde, south of Berlin, shows the German Therme version. The building holds a sports pool and a thermal bath, and they follow opposite rules. The sports pool is "always with textile". The Therme, the operator says, is a completely textile-free area: take your swimsuit off as soon as you leave the changing room. The exception is fixed in the timetable: on set days, Wednesday among them, you may bathe with or without a swimsuit. In the restaurants you wear a bath towel or a robe, except at the pool bar.
Another Kristall house, the Kristall Sauna-Wellnesspark in Bad Klosterlausnitz in Thuringia, splits the day instead. For part of each day swimwear is optional everywhere except the three-percent thermal brine pool, and for the rest the pools are textile-free; on Wednesdays and Sundays what the operator calls "mixed bathing", with and without swimwear, runs all day. The saunas are always entered without textiles and with a towel underneath. One more rule from the same page will look familiar to anyone who has been to a German bath: please do not reserve a lounger by leaving your towel on it.
MediTherme in Bochum keeps it short. Its saunas, swimming pools and basins are textile-free as a matter of principle, and you may cover yourself with a sauna towel or a bathrobe whenever you like. A robe is required in the restaurant and in some relaxation rooms. On the restaurant's outdoor terrace, the operator allows shorts with a T-shirt, or a sarong, provided belly, legs and bottom are covered. Children and teenagers come in from fourteen, and only with an adult.
Are textile-free saunas mixed?
In the German-speaking countries, mostly yes. The majority of public saunas there are mixed, according to Wikipedia, with separate areas or days for women at some, and more rarely for men. Single-sex saunas for both sexes are rare. Where a bath wants women to have the sauna to themselves, it says so with a women's day on the weekly schedule or a separate women's cabin, and the schedule is published.
Finland, the country that gave the sauna its name, is different in a way that surprises Germans as much as anyone. Finns, Wikipedia says, usually prefer to bathe naked rather than in a swimsuit or towel, and families bathe together in the home sauna. Damp towels on the bench are often thought unhygienic there, so people sit on linen cloths, disposable covers or nothing.
Further south and west the default flips. Mixed saunas are rare in Britain and France, and in much of southern Europe a sauna inside a spa is a swimsuit room. If you are coming from one of those traditions to a German or Belgian bath, the difference is real. It is also the kind of thing that feels enormous for the first five minutes and unremarkable after twenty.
How do I know whether a sauna is textile-free?
Look on the operator's site before you go, under the house rules (Hausordnung, Badeordnung, saunaregels) or the page for first-time visitors. Every bath named here publishes its rule in a sentence or two, and the sentence is usually more precise than any symbol at the door.
Learn four words. Textilfrei means without swimwear. Mit Textil or Badebekleidung means with it. Wahlweise mit oder ohne Textil means your choice. FKK is the older word for the same thing as textile-free, used more for beaches and clubs than for saunas. In Flemish and Dutch, naaktsauna is a naked sauna and badpakkendag is a swimwear day.
Then check the day and the hour. The Friedrichsbad turns on the weekday, Bad Klosterlausnitz on the clock, Ludwigsfelde on both. If you prefer one way or the other, the timetable lets you choose, and nobody at the desk will ask why.
Finally, assume the pool and the sauna differ until the house says otherwise. A large Therme can have a swimwear pool hall and a textile-free sauna garden on the same ticket.
What a first visit looks like
You change in the changing room. In most German baths you leave your swimsuit in the locker if you are going straight to the sauna area, and walk out in a bathrobe with a towel over your arm. Katara asks for two large towels, a bathrobe and slippers, and the slippers are compulsory; you can buy them at reception. Most baths rent robes and towels if you forget.
Before the first cabin you shower, without exception. Inside, you spread your towel so that no part of you touches the wood, sit or lie on it, and stay quiet. Wikipedia's description of German sauna etiquette notes that loud conversation is discouraged, because the sauna is seen as a place for recovery rather than socialising. During an Aufguss, the scheduled infusion when a sauna attendant pours water on the stones and fans the hot air with a towel, you do not open the door halfway through; heat escapes and the whole room notices. Our guide to sauna types explains the vocabulary.
Between rounds you cool off in a cold plunge or shower, wrap up again and lie down. The robe goes on every time you leave a cabin and comes off when you go into the next one. That rhythm is most of what a sauna afternoon is. Nobody is there to be looked at, and staring is the one thing that really breaks the etiquette.
At the Friedrichsbad the whole thing is laid out for you as a circuit, and the operator suggests allowing about three hours. You go from thermal showers to a warm-air room at 54 °C, a hot-air room at 68 °C, a soap-and-brush massage on certain days, two thermal steam rooms, a sequence of pools that steps down from 36 °C to a 28 °C movement pool, and finally an 18 °C cold bath, before a cream, a warmed sheet in the relaxation room and tea in the reading room. Electronic devices may not be taken in. Children under fourteen are not admitted, and fourteen- to seventeen-year-olds come with an adult. The operator also prints a line it attributes to Mark Twain: after ten minutes you forget time, after twenty the world.
If you have a heart or circulation condition, are pregnant, or are not sure whether hot rooms suit you, ask your doctor first; the temperatures above are the operator's, and so are any claims a bath makes about what its water does. For where the German Thermen are, see our guide to thermal baths in Germany.
The baths listed under this article are the 9 that state a textile-free rule, from the Friedrichsbad under the Florentinerberg to Katara in East Flanders, with 6 of them in Germany. Swimwear days are part of almost every timetable, so if you would like to try one before the other, pick the house, then pick the day.