If you have chance, postpone your holiday to mid-May or early June… The weather will be great from May in Marmaris and Antalya… You can do tracking and swim… Antalya and nearby have various options… Antalya and Marmaris have different type of historic sightseeing Aspendos and Antalya museum reflect the historic richness of Anatolia…
We tend to go last week in September to first in October and have always had good weather overall but with the odd storm etc. I have heard that the further you get into October the cooler it gets,but at least you have the advantage of the sea being warmer (than say in June). I would not be overly worried going to Turkey this time of year, as