To Cape Sounion by bus (I did this trip on 2 occasions) To the Sanctuary of Demeter at Elefsina. You can take a local bus. The site is quite large and there is a good museum. To Marathon by bus; there's not much to see at Marathon, but there are beaches nearby at Rafina. To Chalkis, Evia, by train; you can then catch a local bus and explore parts of Evia.

I have not visited the Monastery at Daphne, but that would be another possible day trip from Athens. You could also visit Mount Hymettus, where there are walking trails. There are tour buses that do Delphi and Mycenae as day tours from Athens, but I would not recommend these.

Ann Widdowson Victoria, BC