For mainland Greece, the Messinian Mani is a good choice and lots of places not too far from the city of Kalamata. Many wonderful memories of Kardamyli, Iam64 , which is a very special village. We had a home above there in Prosilio where the views of the Taygetos mountain range and down to a distant Crete were stupendous. A lovely pebbly beach in Kardamyli - think it's maybe sand in Stoupa - and lots of places to stay ( now with air conditioning). Swimming, relaxing on a beach and near the sea, early morning strolls and moonlit meals - fabulous. Nobody hikes in summer temperatures, especially the recent ones. Best to copy the locals, i.e. keep out of the sun, under vines and umbrellas between 11 - 5. No longer do 'mad dogs and Englishmen' avoid just the midday sun because it gets much hotter in the afternoons.