The Acropolis museum new and well done with lots of stuff from BC no photos allowed, Hadrians Library in ruins, Monastiraki square restaurants and the Flea market, lots of things to see and do here.
I went on a day cruise to Hydra, Poros and Aegina islands, blue skies, warm, clear water, idyllic. Poros also had a shop with 46 flavours of Gelato and the Bitter chocolate was the best, add it to your bucket list hahaha.