Introduction to Conca dei Marini: Conca dei Marini is a small town on the Amalfi Coast in the Province of Salerno, Campania Region, southern Italy. There is a sea cave Emerald Cave (Italian: Grotta dello Smeraldo) near the town. The water surface area in the cave is about 45 × 32 meters. The top of the cave is 24 meters above the water. It is not far from the famous Blue Grotto on Capri Island to the west. Differently, the only entrance to the outside world in the Emerald Cave is located below the water surface. There is no entrance above the water surface. Its existence was not known for many years until it was discovered by a fisherman in 1932.