3XN and Austrian firm GERNER GERNER PLUS unveiled a new aquarium scheme titled “Poseidon's Realm”, which won second place in an international competition of the Schönbrunn Zoo in Vienna (A winner is yet to be announced). Working with aquarium specialists ATT, the team designed the aquarium with an undulating silhouette so that it appears like “a great, mysterious veil” across the zoo's landscape. 

Covering 6,000 m2 (65,000 sq.ft), the building is divided into four levels and topped with a green roof that is embedded within the zoo's path network — plus, the roof houses a bearded vulture aviary. 

The aquarium features a glazed, wave-shaped welcome entrance that leads visitors into a “waterworld” tour. Changing temperatures, ambient sounds, lighting, and ceiling heights add to the experience. The main path widens into smaller bays that lead to individual tanks, creating a more intimate experience between visitors and aquatic life. At the end of the tour is a gift shop and cafe, which open up to an outdoor terrace. The cafe and shop also connect to an event room that includes shark and jellyfish tanks. 

Located in a salt water environment, the aquarium is predominantly constructed from concrete. “To further simplify the construction process, the undulating curved roof form consists of divisible sectors, constructed using standard formwork”, 3XN describes. The aquarium's deep tanks are installed directly on the floor base to ensure optimal load distribution and eliminate the need for elaborate static constructions.