On 4 November 1966, an abnormal occurrence of high tides, rain-swollen rivers and a severe sirocco wind caused the canals to rise to a height of 194 cm or 6 ft 4 in.
After being neglected and quietly deteriorating ever since the defeat of the Venetian Republic by Napoleon about a century and a half prior, Venice was suddenly recognized as a city in urgent need of restoration.
The city remained isolated for 24 hours, and having been unprepared for this type of emergency, more than 75 percent of businesses, shops, and artisans' studios, along with thousands of goods, were either seriously damaged or destroyed completely.
John Pope-Hennessy, a British art historian, detected that the first time the full extent of the city's problems was seen: In response, several national and international organizations began working tirelessly in both Venice and Florence, making remarkable development in conserving countless individual sites.
[4] In combination with measures such as coastal reinforcement, the raising of quaysides, and paving and improvement of the lagoon environment, engineers at Fiat designed the MOSE Project.