While I'm in Athens I'd like to rent a car and get outside the city before continuing on to the Cyclades. What are some great day trips from Athens? I'd consider something overnight as well. I'm interested in archeological/historical sites, but also would be happy just experiencing the countryside, stopping along the way at scenic points, wineries etc.
I would either do Galaxidi which is a wonderful little sea town about 3 hours from Athens, and on the way there stop at Delphiwhich is a major archaeological site in Greece, or go to Limni Euboea which is another little town same distance from Athens but opposite direction. No significant monuments there, just a nice off the beaten track place. Both of these would be better if you decide to stay the night. If not, Attiki offers some options, like Sounion, again with some nice temple there overlooking the Agean sea.
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Nafplio (Nauplio). An easy drive down the big motorway, it's a beautiful Venetian town, and you can check off the fabulous ruins of Mycenae (do Tiryns, as well, nearer, less touristy) and Epidaurus on the way.