La Cité de la Mer is an ocean-themed museum located in Cherbourg, France. It features exhibits on marine exploration, including a large aquarium and a replica of the Titanic that showcases its history. Visitors can also explore the Redoutable, a decommissioned nuclear submarine. The museum aims to educate the public about the ocean and its ecosystems. It offers interactive displays and activities for all ages, making it a popular destination for families. La Cité de la Mer also hosts various events and workshops related to marine science and conservation.