The Haliacmon (Modern Greek: Αλιάκμονας, Aliákmonas; formerly: Ἁλιάκμων, Aliákmon or Haliákmōn; Slavic: Бистрица, Bistrica;) is the longest river in Greece, with a total length of 297 km (185 mi).(In Greece there are two rivers longer than Haliakmon, Maritsa (in Greek Εβρος) and Vardar (in Greek Αξιός), but the length of each one of them in Greek territory is less than that of Haliakmon, which flows entirely in Greece). Haliacmon is the traditional English name for the river, but many sources cite the formerly official Katharevousa version of the name, Aliákmon. Today, the only official variant is the demotic Aliákmonas.