Exposure
In Europe, what qualifies as indecent exposure includes generally at least the exposure of genitalia or anus. In case of women, exposing nipples is not seen as proper conduct, but this is not always considered criminal, and depends on individual countries' nudity laws. For the issue of breastfeeding babies in public, see Breastfeeding in public. The intentional exposure of bare buttocks towards someone, mooning, is a deliberate insult. However, public nudity may be allowed in some circumstances, which vary by country. On nudist beaches and in the changing rooms of swimming pools in some countries, keeping one's clothes on is frowned upon. Here it is good manners to undress. In saunas, the rules about nudity vary according to the country. Because one uses the sauna naked, one brings at least one towel to sit on. In most saunas, one can also rent towels. Also, a kind of flip-flops are worn in saunas, not directly in the sweating rooms or in the steam rooms, but outside in the area for relaxing.
Read more about this topic: Etiquette In Europe