The Cap Blanc Aquarium, is on the outskirts of Sant Antoni, close by the Cala Gració road and it is housed in a sea cave which is variously known as the Cova de ses Llagostes or Cova des Vell Marí. The latter name means monk seal in the Ibizan language and it is so named because in the past these animals sheltered in the cave. The name ses Llagostes derives from the fact that for many years the cave was used to keep any leftover lobsters that the fishermen had been unable to sell. In the cave interior, which has five small entrances connecting it to the sea, the cavern acts as a giant fish tank where these crustaceans would be kept until there was a greater demand for them, and they were also shipped to Palma, Barcelona and other ports in the Spanish peninsula.
The cave extends over 370 square metres, and can be visited by means of an overhead walkway that looks down over the water, enabling visitors to see the main species that dwell in Ibizan waters, such as grouper, lobster or rays and many others. The aquarium was established in 1989 and also houses the Centre for Recovery of Marine Species (CREM), so that at times it is possible to catch sight of some animal that is under observation before it is returned to the sea. The most common creatures are marine turtles. There is a small terrace literally on the edge of the sea where you can have a drink. On summer nights throughout the week, spit roasted sardines are served there locally referred to as sardinadas.
