Passing by boat the bay of Koroni one meets an island complex, the Messenian Oinousses, consisting of Schiza, Sapientza, Venetiko, and Aghia Marina. Wild, amidst the waves, steep, but with small rocky passages and green waters.
The area is incorporated in the Natura 2000 Network since the deepest point of the Mediterranean sea is located here, known as the "Oinousses Trench" or "Calypso Deep" with a depth of 5,121 m. The largest islands are Schiza and Sapientza. Schiza is renowned for two things: for its oak trees, used by the ship-makers of Methoni and for the cave of the "Black Hole" that has not been investigated yet and stimulates our imagination with the stories it inspires about its use in the past. Maybe it was a pirates' hide-out? Did they hid treasures here? A cave of gods and fairies? The legendary narrations are rich but not confirmed. Maybe we will never know. However, the cave allures the visitors/explorers, the divers, the swimmers.
Sapientza is an island of lush vegetation, with a rich flora and fauna. Here we find the unique in the Mediterranean forest of perennial hollies and arbutus which reach heights beyond ten meters. The great zoological importance of the island is highlighted by the bottlenose dolphin, the Mediterranean monk seal and the loggerhead sea turtle. The famous Cretan goat Kri-kri lives here, as well as many bird species. Researchers and visitors are mystified by the beauty of the landscape and its harmony with nature.