Omonoia Square (Greek: Πλατεία Ομονοίας, Plateía Omonoías, pronounced [plaˈtia omoˈnias], "Concord Square", often simply referred to as Omónia [oˈmonia]) is a central square in Athens. It marks the northern corner of the downtown area defined by the city plans of the 19th century, and is one of the city's principal traffic hubs.