The Djurgården ("The Animal garden") island has been royal property since centuries, and had been used as a zoological garden since the 16th century. The north-western edge of the island was a shipyard from the 18th century to the 1970s. In 1891, the Skansen open-air museum was founded. As the island hosted an exhibition in 1897, several other museums and pavilions were built. Many of them have been torn down; Nordiska Museet is the largest remainder of the exhibition. While Djurgården contains several of Stockholm's most expensive private properties, most of the island is open to the public. Though the natural and cultural environment is protected by strict laws, developments are under way to meet the expectations of travellers.