Dec 24, 2019 - 10:21 PM
I have been to several Swiss spas but only Leukerbad of the ones you are considering and liked it very much. If you are from an English speaking country you may or may not be familiar with the local spa etiquette and it is fine to ask if your not sure.
There may not be any universal rules but we found most places don’t allow swimsuit in the dry saunas and in wet saunas (whirlpools) swimsuits may be optional in some and not allowed in others. Communal showers around the saunas were common as well. They have a very relaxed attitude towards nudity as is common in German speaking areas but somewhat less common to those of us from the US and GB. However we adapted quickly as most do.