The city was named after its mythical founder NAFPLIA – the son of the God Poseidon. For a long time the city served as the port of the neighbouring Argos. In the middle ages Nafplion bought the Venetians, and when the Turks it was the capital of the province sea. In 1829-1834 years the city was the capital of independent Greece.

The city has three fortresses. The fortress of Bourtzi was built on the island by the Venetians and in 1930 was the place of residence urban executioner. The fortress guarded the passage in the Gulf and in the case of danger he blocked it with outstretched in the water circuit. The Akronafplia fortress (the second name "EC Calais") stands on a hill above the town. Over the gate of the XV century, you can see the remarkable bas-relief of the Venetian lion. Nearby is the ancient Acropolis. The Palamidi fortress was built in 1710-ies. It is the largest fortress in Greece, however it was taken twice by the Turks in 1715 and the Greek insurgents in 1822.

The Church of the Transfiguration was initially a Byzantine monastic Church, then a mosque, now it is the Catholic Church. The town also has an Archaeological Museum and folk Museum.