The Aquarium complex is divided into 5 smaller aquaria, each with a different theme: Mediterranean, tropical, miniature, planeta aqua and the oceanarium. Mediterranean and tropical concentrate on sealife from these areas, and the Barcelona Aquarium is a world leader on Mediterranean sealife. The miniature tanks focus on small marine life and the planeta aqua on sealife in extreme conditions, but the most famous is the oceanarium, unique in Europe, a huge tank 36 metres across and 5 metres deep full of large ocean species. There is a walk-through tunnel so visitors have the impression of walking on the seabed. As well as visits the Aquarium has activity days and events (e.g. diving with sharks) and you can subscribe to a newsletter on the website. There is a shop and café. For current opening times and entrance fees consult the website. The Aquarium is on the seafront and well served by buses, tourist buses and underground.