It is one of the two wetlands of Eastern Peloponnisos – the other is the one of Fokianos. It is 4km far from Astros and it is a shelter of migratory birds. The flora of the region is also extremely important. The lake is supplied with water of springs and lead to the gulp of Astros through two canals. With the ecological park of Parnonas, it has been placed to Natura 2000 and it is a preserved region. The environmental importance of the lake is huge as it is said that there was the old port of Astros. The water of the lake is brackish and has healing properties because of the sulfides that contain it. This water is suitable for those who have rheumatic and other diseases. Apart from the Lake of Moustos, there is a smaller lake of Herronisiou, that extends in 20m and its water gushes from the hill. The lake leads directly to the sea.