The Lake is located 2,5 km long from the sea, into the hills. It is created by the hindrance of underground water, from the impenetrable rocks and the sprawl of natural ground. The Lake's deeper point reaches the 22 metres and her level changes, depending on the season: Winter it is decreased and at summertime that snowballs melt goes up. Actually, it is a big bended surface that is supplied by his one side with water because his porosities of soil while from opposite gets dry because the nature of rocks.
The Lake is referred from the ancient ages with the name "korisia". According to this, it is believed that there was existed a holy in her banks, for the honour of Korisia Athina. However the lake was named by the Arabian conquerors "Koyrna's" that in the Arabics means "bath or lake". The dark colour that waters of lake take, as mirrored of the mountainous volumes, appears that it scared the persons, that had created a legend of this.