Adrian is a form of the Latin given name Adrianus or Hadrianus. Its ultimate origin is most likely via the former river Adria from the Venetic and Illyrian word adur, meaning 'sea' or 'water'. The Adria was until the 8th century BC the main channel of the Po River into the Adriatic Sea but ceased to exist before the 1st century BC. Hecataeus of Miletus (c.550 - c.476 BC) asserted that both the Etruscan harbor city of Adria and the Adriatic Sea had been named after it. Emperor Hadrian's family was named after the city or region of Adria/Hadria, now Atri, in Picenum, which most likely started as an Etruscan or Greek colony of the older harbor city of the same name.