Patroklos or Gaidouronisi 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 or Patroklou Nesos, after the Ptolemaic admiral Patroclus, who established a fortified base there during the C…Patroklos or Gaidouronisi 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 or Patroklou Nesos, after the Ptolemaic admiral Patroclus, who established a fortified base there during the Chremonidean War.