Bus No 78 operates between the airport and the bus (KTEL) station, and it stops at the train station as well. You will need to cross the whole city from south-east to north -west and depending on the time and the day the ride should take between 40mins to an hour. The buses leave every half hour. You can check the bus timetables at www.oasth.gr
my opinion is to use bus78, instead of a taxi, it will take a bit extra time (but not that much), and it will be so much cheaper.the bus ticket costs 50cents prepaid and 60 on the bus, while the taxi will cost you something between 20-40 euros (i only assume, i have never taken this ride on a taxi). Plus, i tend not to trust greek taxi drivers with foreign travelers. I'm sure it's a minority that has given the profession a bad name, but there are a lot of incidents of rip-offs.

