the canal de brienne in toulouse, france, connects the garonne river with the canal du midi and the canal de garonne

south france midi languedoc canal brienne toulouse french engineering pont jumeaux lock ecluse join atlantic mediterranean construction work greatest world garonne river deux mers terminal pyrenees center town europe architecture outdoor detail connects long southern forms des joining considered one works 17th century tourism tourist attraction europe european tourist tourism attraction travel saint-pierre occitanie south scenery du trail