A World Heritage site is an object of outstanding cultural or natural importance to all mankind. It bears witness in a unique way to the history of the earth and mankind and is considered invaluable and therefore needs to be protected and preserved for all time.
The UN began to discuss the idea of World Heritage sites after the two world wars, when great cultural values were lost. The idea was raised to provide global protection to unique objects and areas.
The Convention Concerning the Protection of the World Cultural and Natural Heritage was adopted by UNESCO (the United Nations Educational, Scientific and Cultural Organization) in 1972. Sweden signed the Convention in 1985 and thereby undertook voluntarily to protect its own World Heritage sites for all time and to support other countries in their efforts to look after their World Heritage sites. By 2012, 190 countries had signed the agreement.
The World Heritage sites are divided into two main groups: cultural heritage and natural heritage. Cultural heritage sites are man-made, while natural ones are unspoilt environments. The Agricultural Landscape of Southern Öland is a cultural heritage site.
The World Heritage sites include spectacular buildings and environments such as the pyramids in Egypt, the Grand Canyon in the USA, the Great Barrier Reef in Australia and other important places such as concentration camps and centres for slave trade.
Link to UNESCO: http://whc.unesco.org/