The 81-hectare Botanical Garden form one of Johannesburg's vital green lungs. The land for the gardens was set aside in 1969 - at the time it was a sports field and golf driving range consisting of bare veld and no trees. Now it consists of large, grassy, open spaces scattered with trees and used by runners, picnickers and dog walkers. It hosts the occasional concert season and kite-flying competitions. Visitors enjoy its special gardens - the Shakespeare Garden, the Rose Garden, the Herb Garden, a Hedge Demonstration Garden and the main arboretum, which houses family groupings of plants and trees of South Africa and the rest of the world. The gardens contain an attractive mix of bunched indigenous and exotics surrounded by lawns, overlooking the 7, 5-hectare Emmarentia Dam, which dates back to the turn of the century, popular with canoeists and boaters. There is also a tea pergola and a floreum for meetings, shows and exhibitions. The dam is fed by two smaller dams above it, which a