Salamis or Salamina is the largest Greek island in the Saronic Gulf, about two kilometres from the coast of Piraeus and about 16 km west of central Athens. The chief city, Salamina, lies in the west-facing core of the crescent on Salamis Bay, which opens into the Saronic Gulf. On the eastern side of the island is its main port, Paloukia, the second largest port in Greece in terms of size, after the port of Piraeus.

The Saronic Gulf or Gulf of Aegina in Greece is formed between the peninsulas of Attica and Argolis and forms part of the Aegean Sea. It defines the eastern side of the isthmus of Corinth, being the eastern terminus of the Corinth Canal, which cuts across the isthmus. The Saronic Islands in the gulf have played a pivotal role in the history of Greece, with the largest, Salamis being the location of a significant naval battle in the Greco-Persian wars. The Megara Gulf makes up the northern end of the Saronic Gulf.