Checking the following codes will get you on your way to the right place for your trip in Greece.

Athens the Capital of Greece: ATH

Athens International Airport is also called Eleftherios Venizelos or Spata.
Athens is also spelled Athina in Greek Latin.

Thessaloniki Airport: SKG

Also called Macedonia or Kratikós Aeroliménas Thessaloníkis “Makedonía” or Mikra Airport.

Heraklion Airport in Crete Island : HER

Heraklion Airport is also called Nikos Kazantzakis.
Heraklion is also spelled Iraklion or Iraklio in Greek Latin.

Chania Airport in Crete Island: CHQ

Chania Airport is also spelled Hania airport, Xania airport, or Khania airport.
Also called Ioannis Daskalogiannis (from the a Cretan revolt Ioannis Daskalogiannis a local hero.)

Corfu Airport in Corfu Island: CFU

Also called Ioannis Kapodistrias. Do not confuse with Ioannis Daskalogiannis at Chania
The Corfu Airport sometimes easily confused with the Chania International Airport (CHQ)

Kavala/Chrysoupoli: KVA

Also called Mega Alexandros or Alexander the Great.

Kefalonia Island Airport : EFL

Also called Odysseus, Ulysses, or Anna Pollatou.

Kos Airport in Kos Island: KGS

Also called Ippokratis or Hippocrates.

Kalamata City Airport: KLX

Kalamata Airport lso called Captain Vassilis Constantakopoulos.

Lemnos Island: LXS

Also called Hephaestus or Ifestos.

Milos Island: MLO

Also called Afrodite or Aphrodite.

Mykonos Airport in Mykonos Island: JMK

Also called Delos or Dilos.

Mytilene (Lesbos) Island: MJT

Also called Odysseas Elitis.

Naxos Island: JNX

Also called Apollon.

Paros Island: PAS

Also called Artemis or Panteleou Paros Airport.

Preveza/Aktio: PVK

Also called Aktion and Lefkada.

Rhodes Airport in Rhodes Island: RHO

More on Rhodes Airport is also called Diagoras.

Samos Island: SMI

Also called Aristarchus of Samos.

Santorini Island: JTR

Santorini Airport is also called Zefiros.

Skiathos Island: JSI

Also called Alexandros Papadiamantis.

Skyros Island: SKU

Also called Aegean.

Syros Island: JSY

Also called Demetrius Vikelas.

Volos: VOL

Also called Nea Anchialos or Volos Central

Zakynthos Island: ZTH

Also called Dionisios Solomos.