What are the katavothres in Kefalonia?

[knicks_fan87]

I've heard a little bit about the phenomenon but I don't know exactly what the katavothres are. Can anyone help out?

 

[mastichas09]

According to greka.com "At Katavothres the sea flows inland and enters sinkholes on the earth that is below sea level. It is assumed that there are caverns below the seabed which is where the water flows in. The mills used to be run in these holes." https://www.greeka.com/ionian/kefalonia/sightseeing/kefalonia-katavothres/

 

[paharo45]

It's such a beautiful natural phenomenon! Look at it in action