Methana (Greek: Μέθανα) is a town and a former municipality on the Peloponnese peninsula, Greece. Since the 2011 local government reform it is part of the municipality Troizinia, of which it is a municipal unit.
Methana is situated on a volcanic (the Methana Volcano) peninsula, attached to the Peloponnese. Administratively, it belongs to the Attica region. The town is located north of the road connecting to the rest of the Peloponnese and Galatas. The highest point is 740 metres (2,428 feet) (Helona Mountain). The municipal unit has a land area of 50.161 square kilometres (19.367 square miles) and a population of 1,657 inhabitants at the 2011 census. The largest settlements besides the town of Methana are Vathý, Megalochóri, Kounoupítsa, Kypséli, Ágioi Theódoroi, and Dritsaíika.
The peninsula is entirely of volcanic origin and contains over 30 volcanic eruption centers. The last volcanic eruption occurred near present-day Kameni Chora in 230 BC and a submarine volcano erupted in 1700. Famous writers such as Ovid, Strabo and Pausanias reported the last volcanic eruption in Methana. The peninsula is the northwesternmost of the arc of the Aegean islands of which the active volcanic areas are Methana, Milos, Santorini and Nisyros. In the future, Methana (and the area of the Saronic gulf) may expect other volcanic eruptions.
The earliest known settlement (near the village of Vathy) dates from 1500–1300 BC. Many ancient sites were identified through the archaeological survey conducted in the 1980s by the University of Liverpool in association with the British School at Athens. The Acropolis Palaiokastro is located near the village of Vathy. The fortress is in Kypseli at the coast Akropolis Oga at the principal pace of Nisaki (Νησάκι, meaning little island). A Mycenaean settlement was excavated by Helene Konstolakis-Jiannopoulou in 1990 along with the chapel of Agios Konstantinos and Elenis. Selected artifacts can be visited in the museums of Poros island and in Piraeus. This site dates between 1500 and 1300 BC. In his History of the Peloponnesian War, Thucydides tells of an Athenian expeditionary force under Nicias that after defeating Corinth (in 425 BC) built a wall across the isthmus to cut the Methana peninsula off from the mainland. In the Hellenistic period, the peninsula became one of the Ptolemaic bases in the Aegean when it was renamed Arsinoe. Traditionally, the population of Methana were Arvanites.