Considering the Sofitel Venezia in Venice?
A VT member wrote the following comment about visiting Venice:
~ Venice Floods ~ by Carnation
You will notice, in the city, piles of metal trestles and planks of wood. They are erected as walking platforms during the seasonal high tides which flood many parts of Venice at regular and irregular intervals. Piazza San Marco is flooded before other areas because under it still runs the Canale Botario which was interred when the Basilica Di San Marco and the Palazzo Ducale were built. When these platforms are not officially needed they are put to other uses, such as picnic tables for daytrippers and as stalls by unlicenced street vendors.
If you should hear 'air-raid' type sirens, then this means they are warning you that the high tide is expected to reach over 1.10 meters above the average sea level, therefore flooding some parts of Venice.