Neptune’s Grotto was discovered in the 18th century by a local fisherman, and it became over time a popular tourist attraction. The cave took its name from the Roman divinity of the sea, Neptune.
Until 1959, the date of completion of the Escala del Cabirol (Roe Deer Staircase), the stairway which descends to the cave on the rocky wall of Capo Caccia, the Neptune’s Grotto could be visited only from the sea, and therefore accessible only in calm sea conditions.
Inside the cave, we can find astounding large rooms with magnificent karst formations, an underground lake and a sandy beach.
The Lake Lamarmora is an underground salt lake with a depth of about 9 meters, a maximum width of 25 meters and a length of 100 meters. The lake has a stalagmite column in the center called Acquasantiera (Stoup), due to the receptacles in the upper part which contain fresh water. On the bottom of the lake, there is a formation of stalagmites called Christmas Tree.
In the cave, we can also find the Hall of Ruins, the Hall of the Royal Palace, with calcitic columns of about 9 meters in height, the Ciottolini Beach (Pebbles Beach) and the Smith Hall or Hall of the Organ, named after an English captain who was one of the first explorers of the grotto. In the center of the Smith Hall, there is a tall column called the Great Organ, whose rock flows resemble organ pipes.
Other interesting components of the cave are the Cupola, a formation of smooth stalagmites joined to the ceiling, the Lace Hall and the Music Stand, a balcony overlooking the lake and the beach.
There are parts in the cave which are reserved only for speleologists and can not be visited by tourists, such as the Funghi Lake (Lake of Mushrooms), the underground tunnel and the Crescent Lake, 70 meters long and 52 metres deep. The total length of the cave is about 4 kilometers, but only a few hundred meters can be visited by the public.
HOW TO GET THERE
The entrance to the grotto is practically at the sea level and is accessible only if the weather and sea conditions allow it. To access it, there are two possibilities – through a stairway of 654 steps that winds along the wall of Capo Caccia, or by boat, with the departure from the Port of Alghero or from the pier of the Dragunara in Porto Conte.
The entry fee to the cave is 13€ and you can visit it every day between 8.00 am and 8.00 pm, with tours starting every fixed hour. A boat trip to the grotto and back from the Port of Alghero takes about one hour and a ticket costs about 15€.