a city of Greece, on the E. coast of Attica, situated in a plain of the same name, is said to have been founded by Xuthus, who married the daughter of Erechtheus, and to have derived its name from the hero Marathon. Originally it constituted, along with three other cities, the district of Tetrapolis; but when that district was incorporated by Theseus into the state of Attica, Marathon, as the most important of the four cities, gave its name to the neighbourhood. Here Eurystheus was defeated and slain by Iolaus the Heraclid; and here Theseus slew the furious bull, the pest of the plain (Str. viii.; Ovid, Met. vii. 433). But Marathon is chiefly famous as the battlefield on which the Athenians, in 490 B.C., defeated the Persians, and vindicated the independence of Greece (Herodot. vi. 102.) A monument to the memory of Miltiades, and the two tumuli that covered the slain of the Athenians and Platæans respectively, stood on the field in the time of Pausanias (i. 32). The former of the tumuli, about 600 feet in circumference and 30 in height, is still seen standing in the centre of the plain, about a mile and a half from the shore. (For a minute account of the plain of Marathon, see Colonel Leake's *Demi of Attica*, vol. ii.)