The Madeira Aquarium opened in 2005 in Porto Moniz, next to the harbour. It is housed in the São João Baptista Fort, which was built to protect Porto Moniz from raiding Moors. In 1998, the Porto Moniz Municipal Council bought its ruins, which were restored, keeping its original design but adapting its interior to be used as an aquarium. With about 90 different species of sea animals distributed in 12 tanks (the largest of which contains approximately 500,000 liters of salt water), this tourist attraction will give you a pretty good idea of the various habitats of the island’s marine world. Even if you do not go into the aquarium the outside grounds are beautiful with the facade of the old fort surrounded by the rocky shoreline.