In Portuguese, Oceanario de Lisbona is the largest indoor aquarium in all the European continent and is located on the grounds of the Expo 98 site, in Parque das Nações in Lisbon, Portugal. It has become one of the most famous and most visited attractions of Lisbon and overall Portugal, attracting more than one million visitors each year.
The Oceanarium was first opened in 1998 and the he building that houses it was designed by an American architect. The aquarium holds an amazing collection of marine species, with a total of 16,000 individual creatures of 450 species living inside it. It holds about 25,000 fish, seabirds and mammals in an enormous tank the size of about four Olympic-sized swimming pools, giving the animals a large place to roam about freely.