You MUST see the prices on /www.easyjet.com/
There is no comparison. I am going to Athens one way for £29. (about $46.00 US) If you don’t mind getting to Luton airport which is outside of the main city you will save big time. This airline gives a discount if you book on-line (electronicly) take your reference # and passport to the desk at the airport to get your boarding pass then take off!!