The Jizera (German: Iser; Polish: Izera) is a river that begins on the border between Poland and the Czech Republic (in Silesia) and ends in Central Bohemia. Like some other names in Bohemia, the name Jizera is of Celtic origin, as the Celtic Boii (hence the Germanic word Bohemia, home of the Boii) lived in the area before the Roman times (see also the Isar in Germany and the Isère in France) before assimilation by the Marcomanni and later Germanic and West Slavic peoples.