The building was constructed for the International Exposition of 1906 and designed by Architect Sebastiano Locati. In Liberty style, the Station houses forms and decorations of an aquatic theme in "Maiolica". Damaged in 1943, during the war, the building remains intact thanks to diverse restorations. At the borders of Sempione Park (which reflect the architectural symmetry), rises the Civic Arena. One of the oldest in the world, the Acquario e Civica Stazione Idrobiologica houses 36 tanks with 100 species of aquatic animals: fish, shellfish, molluscs, spiny invertebrates represent the Mediterranean, the Italian fresh-water fauna, and the tropical water animals. In the posterior gardens, currently under reconstruction, Milanese aquatic environments have been reconstructed, including the surging fountain, the pond, the spring, the marsh, the hollow and the courtyard. The media library and library, dedicated to aquatic science, offer 10,000 books, 14,500 extracts, 718 periodicals, 250 videocassettes, 600 slides, and scholarly collections on fish and molluscs. Institute publications, scientific journal: "Quaderni della stazione idrobiologica di Milano". There are specific educational activities organized for scholars.