Cephalonia (Kefalonia) is the largest Greek island of the Ionian Sea in Greece.The island got its name from the mythical hunter Cephalus, son of god Hermes and the princess Herse. Cephalus went into exile after killing his wife Procris accidentally while on the hunt. There, he met Amphitryon, the king of Athens, and offered to help him in the war against the original inhabitants of Cephalonia.
After the victory, Amphitryon donated the island to Cephalus. Four of sons Cephalus, Sami, Pronoi, Pali and Krani, gave their names to the four cities of Kefalonia, which were independent republics and had their own currencies. For this reason, the island was mentioned as Tetrapolis (four cities) in ancient times. These four cities can be found in Kefalonia until today.