Which Athens Port is Closest to Airport?
The Athens Port that is closest to the Athens International Airport is the Rafina Port. The Rafina Port is 28Kms away from Athens Airport and it will take you around 30 minutes to reach it. Athens has also another port which is called Piraeus Port which is much further away from the Airport.
You can also get a 3-days in Athens Travel Guide, here, which can help you enormously to plan your trip to Athens.