Aquarium Pula is the most visited public aquarium in Croatia whose mission is to show the beauty and diversity of the underwater world and emphasize the need for its protection. The aquarium itself is settled in a 130-year-old fort Verudela, part of the once-mighty Austro – Hungarian defence complex Fortress Pula, where the centennial military history of Pula is combined in a unique way with the richness of the Adriatic. Fort Verudela, named after the peninsula where it was built (3 km from the center of Pula), has been in a process of conversion into an aquarium since 2002. and is now home to some 200 animal species. Sharks, jellyfish and seahorses are the most sought after inhabitants, with the Marine turtle rescue center, our biggest contribution to marine conservation, as something not to be missed. The fort’s roof, besides offering a magnificent view of Pula and the sea, from 2017. displays a massive steel dome placed over the old artillery block. The dome represents the final stage of our project where we reconstructed the central part of the fort and added 3 new tanks (50 000 liters each), greatly expanding our display.