Eretria is a town in Euboea, Greece, facing the coast of Attica across the narrow South Euboean Gulf. It was an important Greek polis in the 6th and 5th century BC, mentioned by many famous writers and actively involved in significant historical events. Excavations of the ancient city began in the 1890s and have been conducted since 1964 by the Greek Archaeological Service and the Swiss School of Archaeology in Greece.