The sexes alternate between the daysMonday, Wednesday and Friday are for the ladies, while Tuesday, Thursday and Saturday are gents' days. Sunday's split between the two, with gents from 8-9 in the morning and ladies for the rest of the day.
Leave your swimsuit at home (you can swim with yours on, but be daring and bare it all)! Your entrance fee includes a towel, and then you hop in the shower to rinse off before steaming along with a dozen or so of your new closest Finnish friends in the saunas.
The Uimahalli has several different saunas, each at a different temperature, and your compatriots will be happy to take care of splashing some the bucket of water onto the hot rocks of the sauna to envelop you in muscle-relaxing steam.
Take your cue from the Finns and cool off in the cavernous space of the main swimming pool, a gorgeous triumph of 1920s classical style. (A style that belies the fairly boring exterior, in fairness.)
Relax afterwards on a lounger chair, or pick up something to drink from the café.
You'll find it at number 21b Yrjönkatu in central Helsinki, just off Mannerheimintie. Look for the vertical sign!
[Photos: Obviously, the all-nude Uimahalli is a no-photos zone! Exterior: John Walton/Jaunted. Interior: VisitFinland.com]