Patroklos (Greek: Πάτροκλος) or Gaidouronisi (Γαϊδουρονήσι, "donkey island") is a small, private island located in the Saronic Gulf, Greece. It is situated about 65 km from Athens and 3 km from Sounion and is part of the Attica region.
In ancient times, the island was known as Patroklou Charax (Πατρόκλου χάραξ, meaning "Camp of Patroclus") or Patroklou Nesos (Πατρόκλου νῆσος, meaning "Island of Patroclus"), after the Ptolemaic admiral Patroclus, who established a fortified base there during the Chremonidean War.[1]