Nausicaà Centre National de la Mer, Public aquarium in Boulogne-sur-Mer, France

Nausicaà Centre National de la Mer is a marine discovery centre on the Channel coast at Boulogne-sur-Mer, between the beach and the fishing port. Its white buildings carry the blue Nausicaà sign and a large blue sphere, with a glass curtain wall rising to a peaked roof. Inside, 10,000 m² of staged exhibits hold 17 million litres of seawater and about 58,000 animals, grouped into the galleries "Mankind and Shores" and "The High Seas".

Guy Lengagne, mayor of Boulogne-sur-Mer, proposed a sea centre on the site of the town's old casino; the casino building was demolished rather than converted. Architect Jacques Rougerie was chosen in 1984, construction ran from 1987, and the centre opened on 18 May 1991 as Nausicaá. A 1998 expansion doubled the exhibition area, and the 2018 "High Seas" gallery added a 10,000 m³ tank.

The name comes from Nausicaa, a princess in Homer's Odyssey known for her connection to the sea. Today, school groups from across northern France come here to walk through the galleries and learn about marine life.

The aquarium opens daily and sits within walking distance from the center of Boulogne-sur-Mer. All floors are accessible by lift, making the route through the building manageable for wheelchair users and families with strollers.

One tank in the building replicates the ecosystem of Colombia's Malpelo Island, an isolated rock formation in the Pacific that is rarely shown in aquariums. Visitors see sharks and other open-ocean fish there that are normally only observed by divers at great depths.