Poros is a small island separated by a strait of just 200 meters from the shore of the Peloponnese. In the antiquity, the island hosted an asylum dedicated to Poseidon the god of sea, and was a naval base of the region. In modern times the first naval base of Greece was established there after independence in the 19^th century.

The town of Poros is built on the slopes of a hill and is nowadays a popular summer resort.