Ponte sobre o Rio Vouga, Sernada do Vouga - Portugal
The combined rail and road bridge in Sernada do Vouga. If a train has to go over the bridge, it's locked for all cars as the rails are in the centre of the road and there isn't enough space for cars at either side. As soon as the train is on the bridge the cars going in the same direction are allowed to ride behind it.
The photo was taken from a train that just passed the bridge