This is a place you should visit at least once in your life: the only way to truly admire the beauty of this place and perceive its charm is in person. Neptune’s grotto is one of the largest marine caves in Italy and one of the most captivating gems of nature in the Mediterranean. The grotto was formed about two million years ago: inside, you will see rooms with astounding karst formations, a white sandy beach and a huge underground lake. The Coves de Neptú (in Catalan language) was discovered by a fisherman in the 18th century and soon became a tourist attraction. It extends horizontally for about four kilometres on the same level as the surface of the sea. Neptune’s grotto is located 24 km from Alghero and is the pride and joy of the marine protected area of Capo Caccia-Isola Piana, inside the Porto Conte Park.