Spain and Portugal - River Duro - View down river - scrubland , tall chimney on left , terraced ? hill side on right , hills in background. Part of Box 149 Boswell collection - Portugal and Spain. The name, Latinized Durius, may have come from the Celtic tribes that inhabited the area before Roman times: the Celtic root is *dubro- and in modern Welsh d?r is 'water' with cognate dobhar in Irish. In Roman times, the river was personified as a god, Durius.