The United Nations Educational, Scientific and Cultural Organization (UNESCO) designates World Heritage Sites, listing places of outstanding universal value to cultural or natural heritage. These must be nominated by countries which are signatories to the UNESCO World Heritage Convention, established in 1972. Cultural heritage consists of monuments, groups of buildings, and sites. Natural features, geological and physiographical formations, and natural sites which are important from the point of view of science, conservation or natural beauty, are defined as natural heritage.