Foster + Partners is celebrating 15 years since the completion of Elephant House at Copenhagen Zoo. The building provides the elephants with a healthy, stimulating environment and creates easily accessible spaces from which visitors can see and enjoy them.Back in 2001, initial sketches and early models were used to help raise funds for the new building. Once the zoo had achieved their fundraising targets, Foster + Partners was asked to take designs to the next level.During the second phase of the project, Foster + Partners had to think about the technicalities of designing a space for these magnificent animals. The building had to take on board their strength and intelligence, while optimising health and comfort. Foster + Partners worked with the mechanical engineers, Rambøll, and the structural engineers, Buro Happold, to design an ‘elephant proof’ structure. The building has excessively high loads and thick walls, which also help with insulation during the cold Copenhagen winters.In the spring of 2008, the elephants moved from the old Elephant House into their new home. The 49-year-old male elephant Chieng Mai was the first elephant to move into his new surroundings. He was followed by the female elephants Inda, Surin, Kungrao and Ida with her calf Gandhi. The last to be moved was the young bull, Tonsak.