There is no uniform view on who came up with an idea of an open-air museum. Such initiatives were taken in a number of countries at the same time. However, this concept materialised in Scandinavian countries in the second half of the 19th century. It was implemented by Artur Hazelius (1833-1901), a Swedish folk culture researcher. An open air museum, the first in the world, was ceremonially opened in Stockholm, in 1891.