Pythagoreio (Πυθαγόρειο) is a municipality of Samos. It is the largest municipality in land area on Samos, at 164.662 km² and has a population of 9,000 people (2001) .It is the main tourist resort on the island.
The capital of the municipality is the town of Pythagoreio, formerly known as Tigani. The town was renamed in 1955 to honour the local-born mathematician and philosopher Pythagoras.
The port of the town is considered to be the oldest man-made port of the Mediterranean Sea.
Many yachts and sailing boats moor here in the large, picturesque harbour.
There are several archeological sites worth visiting in the area. Other sites of Pythagorion are the statue of Pythagoras, the Castle of Likourgos, the Church of Metamorphosis, The Ephpalinos Tunnel, the Church of Spiliani with its chapel in the cave, the Roman Baths, The Lake of Glifada.
Pythagorio, unique cultural jewel of the Aegean, has been declared as an Unesco Cultural World Heritage Site.