The Royal Botanic Gardens is a 75 acre (30-ha) natural land mass wrapped around the foreshores of Sydney Harbour. Originally established by the First Fleet as a farm, it now contains groves of palm trees, duck ponds, a cactus garden, restaurant, greenhouses, and acres of lawns that combine to form Sydney's finest garden. Founded in 1816, it expanded greatly with the development of agriculture in the 1830's after first encountering difficulties due to the limited agricultural background of the convicts.The collection of plants and shrubbery in the garden come from the Australian wildlife as well as from around the world. Statues and monuments are also scattered throughout the garden. Contained within the garden is the National Herbarium of New South Wales, a research centre for Australian plants. It houses and displays specimens that were collected by Joseph Banks, a botanist on Captain James Cook's First Fleet, which sailed through the east coast of Australia. The Sydney Tropical Centre is unique in that the two pyramid glass houses contain tropical ecosystems and Sydney fernery. It also houses "exotics," which are plants not found locally. The Royal Botanic Gardens often hosts events such as "live theatre under the stars" and open air cinemas throughout the year