https://blog.ricksteves.com/blog/naked-cartoon-characters-in-germany/
"It’s long been a frustration with me as a guide — getting Americans
into spas with naked Europeans."
It's in his blog from 2007, and a quick peak on the tour page and he's still suggesting that you'll have an optional opportunity to get naked during the Best of Germany, Austria and Switzerland tour. I'm all for trying new things, but...
Just how far are you willing to go to live like a local??