**Please Note: 4 years old child will only need a separate ticket for Barcelona City Sightseeing Barcelona Hop-on Hop-off** City Sightseeing Barcelona Hop-on Hop-off Explore and absorb all the major classic sights of Barcelona with the City Sightseeing Traditional Tour double-decker buses. Museum of Modern Art, Port Olympic marina and the ultra-modern urban regeneration area along the coast are essential must-sees for anyone visiting Barcelona! With City Sightseeing Hop Off Hop On tours, you’ll uncover the heart of the city, set at your own pace and convenience. Buses are only ever minutes away. These purpose designed and professional tours guide you to gain the most from your city experience. Barcelona Aquarium – L’Aquarium Barcelona Aquarium has got to be the world’s most important Mediterranean themed aquarium and a must to visit whilst you are in this fabulous city. The spectacular Oceanarium is the only one of its kind in Europe, is the largest tank and the one with the largest number of species in the aquarium. With a diameter of 36 metres and 5 metres in depth, it contains 4,500 square metres of water and contains many diverse species.