Athens Airport

There are to ways to Tranfer from and to Athens International Airport El. Venizelos with public transportation the first one is the Metro
The Athens Metro is an underground rapid transit system serving the capital of Greece. Proastiakos is similar transit system that connects Athens with its eastern suburbs and the airport
Take metro line 3(Aghia Marina – Douk. Plakentrias – Athens International Airport) Which connects the Athens airport with the city center. Airport timetable from all the metro stations of the line 3 can be found here 
**The train runs every 30 minutes from 6:30 a.m. to 11:30 p.m**
The second way is the Bus 
1) X95 Syntagma Square – Athens Airport:Use this bus if you want to get to Athens Airport from Syntagma or to get to Syntagma Square from the Airport
2) X96 Piraeus – Athens Airport:Use this bus if you want to get to the port from the Airport(it takes about 90 minutes to get there)
3) X93 Kifisou Avenue – Athens Airport: Use this bus to reach the intercity bus station
4) X97 Elliniko – Athens Airport: You can use this bus from the Elliniko metro station to reach the Airport
**Click at the hyperlinks to see more information about the routes&departure times of the buses**