The Liquidrom spa is small yet impressive. Hot and cold pools are tucked away in stunning stone wall surroundings. But get your serious face on - this is for grown ups only. There's no talking in the domed salt-water pool. But it's so dark you can get up to whatever you want - just keep the volume down.

With just a few features on offer, all are done well. But to make most of your 2 hour, 17.50 euro session, do naked sauna Aufguß:

If an old man offers you salt at the Liquidrom, whip off your swimming suit, rub salt all over body and wait patiently. Water will be poured over hot sauna coals. Then, cue the hottest air being whipped at your naked, salted body by a hairy 70-year-old armed with a towel. Any worries re: nakedness or erections will be long gone. Make sure you've got 30-45 mins to rest afterwards.

For a first timer, it's easy to waste time finding changing rooms, deciphering the locker system and finding the main attractions. But
it's an extraordinary experience if you have the courage to try everything on offer. Massages cost extra. Tip: Bring your own towels.