I'm going to Greece!

[readsintrees.livejournal.com]

I'm going to be going to Greece at the end of August for about a week! The birthplace of Eddis/Attolia/Sounis!

I know MWT has visited Greece many times, but I can't seem to find all of her Tumblr posts easily. Anyone have suggestion for sights (or sites) that I MUST see while there that are either in Athens (where I'll be arriving), Thessaloniki (where I'll be staying), or anywhere in between? We'll only be on foot or public transportation, so unfortunately places well off the beaten path aren't an option.