According to the Convention Concerning the Protection of the World Cultural and Natural Heritage (commonly known as the 'World Heritage Convention'), "cultural heritage" is a monument, group of buildings or site of historical, aesthetic, archaeological, scientific, ethnological or anthropological value. "Natural heritage" designates outstanding physical, biological, and geological features; habitats of threatened plants or animal species and areas of value on scientific or aesthetic grounds or from the point of view of conservation.
The most significant feature of the Convention is to link together in a single document the concepts of nature conservation and the preservation of cultural sites. Nature and culture are complementary and cultural identity is strongly related to the natural environment in which it develops.
This is done through the World Heritage List. There are 730 properties which the World Heritage Committee has inscribed on the World Heritage List (At the 40th anniversary of the World Heritage Convention in 2012, there were 936 sites inscribed in the List for their outstanding universal value in 153 countries around the world).
Cultural heritage should:
- represent a masterpiece of human creative genius, or
- exhibit an important interchange of human values over a span of time or within a cultural area of the world, on developments in architecture or technology, monumental arts, town planning or landscape design, or
- bear a unique or at least exceptional testimony to a cultural tradition or to a civilization which is living or has disappeared, or
- be an outstanding example of a type of building or architectural or technological ensemble, or landscape which illustrates a significant stage or significant stages in human history, or
- be an outstanding example of a traditional human settlement or land-use which is representative of a culture or cultures, especially when it has become vulnerable under the impact of irreversible change, or
- be directly or tangibly associated with events or living traditions, with ideas or with beliefs, or with artistic and literary works of outstanding universal significance (a criterion used only in exceptional circumstances, and together with other criteria).
- Equally important is the authenticity of the site and the way it is protected and managed.
Natural properties should:
- be outstanding examples representing major stages of the earth's history, including the record of life, significant ongoing geological processes in the development of landforms, or significant geomorphic or physiographic features, or
- be outstanding examples representing significant ongoing ecological and biological processes in the evolution and development of terrestrial, fresh water, coastal and marine ecosystems and communities of plants and animals,
- contain superlative natural phenomena or areas of exceptional natural beauty and aesthetic importance, or
- contain the most important and significant natural habitats for in situ conservation of biological diversity, including those containing threatened species of outstanding universal value from the point of view of science or conservation.
The protection, management and integrity of the site are also important considerations.
Mixed sites have both outstanding natural and cultural values. Since 1992 significant interactions between people and the natural environment have been recognized as cultural landscapes.