Spetses (Modern Greek: Σπέτσες, Katharevousa: Σπέτσαι, Spetsai, Ancient: Πιτυούσσα, «Pityoussa») is an island and a municipality in the Islands regional unit, Attica, Greece. It is sometimes included as one of the Saronic Islands. Until 1948, it was part of the old prefecture of Argolidocorinthia, which is now split into Argolis and Corinthia. In ancient times, it was known as Pityoussa, and later as Petses.
The island is now an independent municipality (pop. 4,027), with no internal boundaries within the municipality. The town of Spetses (pop. 4,001 in 2011) is the only large settlement on the island. The other settlements on the island are Moní Agíon Pánton (pop. 0), Ligonéri (4), Ágioi Anárgyroi (18), Kouzoúnos (4). Also part of the Municipality of Spetses are the islands of Spetsopoula, Falkonera, and Velopoula (all uninhabited).
An unusual aspect of Spetses is the absence of private automobiles in the town limits. The most common modes of transport are walking, horse-drawn carriages, bicycles, mopeds, and motorcycles. Only taxis and delivery vehicles are allowed in the downtown area. Ferries and high-speed hydrofoils arrive regularly from Piraeus. Trails encircle the island and total about 25 to 30 km. Beaches closest to the town of Spetses include: Agios Mamas in the center of town; and Kaíki (previously College) beach 1 km to the northwest and Agia Marina 2 km to the south, both of which offer water-sports. Public buses serve beaches further outside of town, including Zogeria, Agioi Anargiroi, and Agia Paraskevi.