there are many recent finds of houses and cities under 10-20 meters of water
These are ANCIENT cities and must be from a very long time ago when sea levels where that much lower
if you look at the Atlentic ocean, it alwasy seemed odd to me that the Atlantic Shelf went out so far and then suddenly dropped off... It looked like the sea level was at that point for a long long time and then rose ... 20 meters
Giving us our current shoreline
TIDES
Today, Venice is a city in northeastern Italy sited on a group of 118 small islands separated by canals and linked by bridges to the mainland and each other.