Because most of the city's traffic goes along the Canal rather than across it, only one bridge crossed the canal until the 19th century, the Rialto Bridge. There are currently three more bridges, the Ponte degliScalzi, the Ponte dell'Accademia, and the recent, controversial Ponte dellaCostituzione, designed by Santiago Calatrava, connecting the train station to Piazzale Roma, one of the few places in Venice where buses and cars can enter