The Acquario Civico di Milano is the third-oldest aquarium in Europe still in operation, founded in 1906 to celebrate the opening of the Sempione Tunnel (Traforo del Sempione) during Milan's grand International Exposition. Among all the pavilions and structures erected for that world-class event, this aquarium stands as the sole surviving building — a remarkable fact that makes it both a scientific institution and a living monument to an entire era of civic ambition. Its longevity speaks to the city's enduring commitment to public education and natural science.
The building itself is a distinguished example of Liberty architecture — Italy's interpretation of Art Nouveau — designed by architect Sebastiano Locati. Its façade is adorned with elaborate ceramic and majolica tiles depicting marine creatures: fish, eels, crabs, and seahorses rendered in vivid glazed detail. The sculptural decoration is not merely ornamental; it functions as a kind of outdoor bestiary, preparing visitors for what lies inside. The structure sits within Parco Sempione, positioned between the Castello Sforzesco and the Arco della Pace, making it one of the most contextually rich cultural sites in the city.
Inside, the aquarium houses dozens of tanks displaying Mediterranean coastal species alongside freshwater inhabitants of Italian rivers and lakes. Visitors encounter moray eels, octopuses, sea bream, cuttlefish, and a variety of invertebrates in carefully maintained salt and freshwater environments. The interior retains much of its early-twentieth-century atmosphere — cast-iron structural elements, arched ceilings, and the soft, filtered light characteristic of historic aquarium halls — while the scientific stations have been progressively updated to support active hydrobiological research through its Stazione Idrobiologica.
Admission is affordable and the scale of the aquarium is intimate enough to explore thoroughly in 60–90 minutes, making it an ideal stop for families and anyone with an interest in architectural history or marine biology. Crowds are consistently lighter than at Milan's major art museums, and mornings on weekdays offer a particularly unhurried experience. The aquarium is a short walk from the Cadorna or Lanza metro stations, and combining a visit with a stroll through Parco Sempione or a stop at the adjacent Castello Sforzesco requires no extra transit at all.
