Greece follows the Schengen Agreement provision and the subsequent acquis concerning short term visa issues stays of up to three (3) months in the Schengen area.
The citizens of these countries are not subject to border controls within the common area (airlines or other carriers require identification – I.D. card or passport or any other piece of identification issued by a public authority). Citizens of the EU countries do not need a visa to enter Greece (and the Schengen area).
Athens International Airport: www.aia.gr
Visa information: www.mfa.gr/en/visas/