Designed to look like a whirlpool from above, Copenhagen's aluminium-clad aquarium is the largest in northern Europe. The space is divided into climatic and geographic sections, the most spectacular of which is 'Ocean/Coral Reef'; home to swarms of Technicolor tropical fish, the exhibition features a massive 4-million-litre tank brimming with sharks, stingrays and other majestic creatures. If possible, visit the aquarium on a Monday evening when it's at its quietest and most evocative.
The Blue Planet is also home to a notable cafe. The complex lies 7km southeast of central Copenhagen and is easily reached by public bus, metro or using the free Den Blå Planet shuttle bus, which departs six times daily from Vesterbrogade 6, opposite Copenhagen's central train station. See the aquarium website for shuttle bus departure times.