Austria has had a presence in Expos as early as the Great Exhibition of 1851 in London. In 1873, a World Expo was organised in Vienna, attracting over 7 million visitors and showcasing the works of 35 countries. Austria joined the BIE in 1947 and has continued to be an active participant in International Expos, with Horticultural Expos being hosted in Vienna in both 1964 and 1974.