For one day the canals are closed and fleets of row boats take to the water. As temperatures soar, Venetians and visitors turn out in their thousands to celebrate the ancient tradition of rowing. At the same time, the police try to rein in speeding motor boats while, on the city's outskirts, an enormous anti-flood system is being built. As the team prepares to lower millions of pounds of technology weighing over 20 tons into the Venice lagoon, nerves are mounting. Without it, Venice is at risk of disappearing under the water. Show less