Tetrapolis (Greek: ) comprised one of the twelve districts into which Attica was divided before the time of Theseus. The district was on a plain in the northeastern part of Attica and contained four cities: Marathon (), Probalinthus (), Tricorythus (), and Oenoe (). Stephanus of Byzantium claimed "Huttēnia" (Ὑττηνία) was its name among the Pelasgoi. The name persisted as a reference to the cities, which shared a religious calendar. Following the reforms of Cleisthenes in 508, the cities (demes) of Marathon, Oenoe, and Tricorythus were organised into a single trittys along with the city of Rhamnous, whilst Probalinthus belonged to another trittyes; nonetheless, the former was often still referred to as the Tetrapolis despite not including Probalinthus.