Not too sure yet. Guess just a lot of walking around the city, really. Not so much on the outskirts of town? I'll be with my brother for most of the time and I wanted to catch up with another guy I know there, but if I'm alone and bored, sure this won't be a problem.
Ah, cool. I'm sure there's plenty to do around the central city. I know I could kill hours in the Botanical Gardens and the National Gallery - I just need to drag somebody along one day. Otherwise, my knowledge of stuff to do in this city is rather unfortunately limited to where you can see cool railed stuff!
I can just see you ending up in the most Greek parts of the city and disappearing for a couple of days ...