Very impressive, this giant vortex at the Barrage between Saint Malo and Dinant in France (Barrage de la Rance). At the right time of day, you can see it just from the dam. We recorded this vortex during our holiday trip in august 2013 when we visited Mont Saint-Michel and Saint Malo. We caught it by surprise and learned later that it's not always there. I guess it depends on the tide as this damn uses the tides to generate electricity. #vortex #whirlpool