Returning to the main road, you proceed short way (about 300 m) and go towards the Rifugio Marini. Take the little road to the "Rifugio Marini" and you will see a really interesting and beautiful outcrop rock (P.O. 3), consisting of grey coral limestone. These rocks derive from the lithification of an old coral reef (age: Jurassic - Lower Cretaceous) that was in a marine shallow water environment. There are mainly large coral branched colonies (one metre and a half) and look like coral living in an actual tropical reef.