Besides a towel did you use flip flops when you went to outdoor baths in Budapest?
Sure. But don't also forget to bring a swim cap--both for men and ladies.
I'm curious David, why the swim cap?
because they are required? Like many places in Europe.
But not in all Nigel. Wondered why some are formal and some aren't. Significance? Religion? History? Just curious but not curious enough or care enough to look it up.
If you are going to Széchenyi, I believe the cap is only required in the lap pool. Flip flops, towels, caps, etc are all for sale by vendors outside the Széchenyi bath house.