Darwineum Tropical Hall (Tropenhalle), Rostock Zoo

The Darwineum was a long time in the making: according to German Wikipedia, more than ten years of planning preceded the opening of this building, designed to give Rostock Zoo's great apes a new home. The zoo acted as client; Atelier Brückner was responsible for general planning and for the design and scenography of the exhibition, while the architecture was credited to Rasbach Architekten, Inros Lackner AG and the engineering office J. Döhler.

Concrete work began in early June 2011 and the topping-out ceremony took place on 2 December 2011. To keep to a tight schedule, the site ran in three shifts with up to seventy workers at its peak, and a specialist Austrian firm was consulted on the most demanding concrete, notably for the saltwater aquariums. The Darwineum opened on 7 September 2012.

Costing 28.94 million euros, it is the largest building project in the zoo's history. Funding came from the economy, construction and tourism ministry of Mecklenburg-Western Pomerania (22.94 million euros), from loans (4.4 million), from donations (1.45 million) and from the city of Rostock (150,000 euros). A fundraising drive called "Schaffen für die Affen" (roughly, "working for the apes") raised more than a million euros on its own.

The Darwineum brings two exhibition circuits and a large tropical hall together in one complex. At the topping-out the building was described as covering 9,000 m², whereas PSP Architekten Ingenieure, who also list it among their projects, give 10,000 m². The tropical hall at its heart covers 4,000 m² and measures 75 by 55 metres.

It is roofed with air-filled ETFE foil cushions spread over more than 3,000 m². The cushions are grouped into separate "sails" meant to recall the rainforest canopy. The roof admits enough daylight to make artificial lighting unnecessary, along with any simulated day-night cycle. Visitors look into the indoor enclosures from a suspension bridge across the gorilla area or through large floor-to-ceiling windows. Construction called for special formwork for the big concrete planting containers and for saltwater-resistant concrete in the exhibition aquariums. Lighting for the exhibition was designed by Licht Kunst Licht.

The tropical hall is first of all the home of the zoo's great apes. Western lowland gorillas and Bornean orangutans live in enclosures modelled on their natural habitats, alongside gibbons, De Brazza's monkeys, sloths and pygmy marmosets. The zoo also lists Bali starlings, beauty snakes, tree skinks and Fiji iguanas in the hall. The enclosures are densely planted and fitted with small swampy pools, streams and climbing structures; outside, the gorillas have 4,500 m² and the orangutans 3,500 m².

Around the hall, the evolution exhibition is laid out in eight themed bays, with Germany's largest jellyfish kreisel tank, a nautilus aquarium, horseshoe crabs, mudskippers and, in the foyer, Galápagos giant tortoises. Across the whole Darwineum more than eighty animal species are on show.

The Darwineum stands within Rostock Zoo, on Barnstorfer Ring. A visit combines, under one roof, the evolution circuit, from the foyer devoted to Charles Darwin to the closing section on human cultural evolution, with the tropical hall, crossed by the suspension bridge above the gorillas. The orangutans' two large compounds and their climbing frames are best watched from the floor-level windows. Being fully enclosed, the hall suits a rainy or cold day; allow at least an hour for the building before exploring the rest of the zoo.