Thank you for all your replies.
Thanks for the warning @TheSnakeCharmer , I'll be wary of Brian from Hull.
@Bereta were they official nudist beaches?
@AllProperTeaIsTheft I felt very comfortable, not ogled and certainly didn't ogle anyone myself. The other people there were very friendly and chatty - with eye contact.
@SallyWD I can only speak from my limited experience, it was a different feeling swimming without a costume, it felt freer than wearing a costume, and the same in the sauna and steam room - no clingy swimsuit soaked in sweat. The feeling of getting air all over was very refreshing.
@mindutopia that's sad and I understand your hard no because of that. The place I went with my friend was welcoming but they also control who attends so I hope that means any pests don't attend.
@TedMullins that sounds like a very interesting festival, though a bit beyond my comfort zone, I think. And I agree with your last sentence, when everyone is naked the nudity is the least interesting thing happening.