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.

The Swiss School of Archaeology in Greece is one of the foreign archaeological institutes operating in Greece. Since 1964, the Swiss archaeologists have been excavating the remains of the ancient site of Eretria (Euboea), a medium-sized city which has extensively contributed to the development and the influence of the Greek civilisation. Hosted in Switzerland by the University of Lausanne, the Swiss School has its head office in Athens, in an Art Nouveau building at Odos Skaramanga 4B. The school has also offices in a 19th-century neoclassical house in Eretria, Odos Apostoli 15.