The wider, curvy brim suggests to me it is a ladies hat.
I tend to not care too much what people think of my attire while on vacation (I wore a homemade tie-dye t-shirt to Hollywood Studios) so I might wear it on vacation anyway.
If you like it then it doesn't really matter what "gender" it was made for, if any.
I'd wear it at the pool or beach, but I'm well beyond giving a crap what other people think about this kind of stuff.