INTERESTING!
Katavothres ~ Argostoli ~ Kefalonia
The famous Katavothres (=swallow-holes) are an extremely rare geological phenomenon. To be honest, we do not know of any other place on Earth, where this could be found! The sea water flows inland to enter sink holes below sea level. In this area the people used the sea water to run mills.
It is rather difficult to understand, where the water goes, when it disappears below sea level. Obviously there are some caverns underground, which the water enters. But after some time they are full and the water should stop flowing. Sea level is a physical border, following the law of communicating tubes, water should flow from the side with the high water level to the side with the low level until both were at the same height. So after some time all caverns should be filled the same height as sea level. In the Mediterranean Sea, there is only very little tide, so this force is no good explanation.
however…
http://www.showcaves.com/english/gr/karst/Katavothres.html
http://www.showcaves.com/english/gr/karst/KatavothresExplain.html