World Heritage Sites are selected to protect and preserve global nature and culture/cultural assets created from human history as treasure for all mankind regardless of national or ethnic boundaries.
The most important objective of this movement is to conserve and hand down various natural environments and cultural assets that are on the verge of extinction or in danger of collapsing. Nevertheless, not all the sites designated for preservation bring back fond memories to us. We should always remember that such negative cultural assets as the Hiroshima Peace Memorial (atomic bomb dome), for example, that remind us of the past shameful deeds of humans are also included on the list.
Today, there also are a number of sites in war-raging areas or are exposed to natural disasters and/or environmental pollutions. Therefore, various approaches are patiently and continuously pursued to maintain and conserve such sites.

The official name of the World Heritage Convention is the "Convention Concerning the Protection of the World Cultural and Natural Heritage."
This is a convention that preserves the world's valuable cultural, natural, and mixed heritages as treasure for all mankind and advocates the important of handing down such assets to the next generation. It was adopted in 1972 at the 17th general meeting of UNESCO. The "World Heritage List" is made based on this convention and those registered on this list become "World Heritage Sites." The very first country to become a member was the United States (1973). As of 1975, 20 countries who applied for membership were officially admitted.
There are 12 World Heritage Sites (four natural and eight cultural sites) that were designated for the first time in history in 1973, for example, Yellowstone National Park (U.S.) and Galapagos Islands (Ecuador).
As of December 2007, there are 184 member nations; Japan ratified the convention to become the 125th member in 1992.
Every year, the World Heritage Committee made up of 21 countries selected by the member nations undertake deliberations and make decisions from the list of various sites recommended by respective countries.

There are three heritage types: cultural, natural, and mixed and all of them must be immovable properties.

●Cultural heritage sites: Structures, architecture, archaeological sites, cultural landscape, etc. with universal values that are significant.

●Natural heritage sites: Regions with endangered species or with landforms, terrestrial formations, ecosystems, and landscape with universal values that are significant.

●Mixed heritage sites: Sites with values belonging to both cultural and natural heritages.

For certain sites to be registered, it is necessary to first find out if the country they are found in has signed the World Heritage Convention. Then, a provisional list containing the names of sites to be potentially registered in the next ten years must be submitted to the UNESCO World Heritage Center. At this time, it is important that the sites on the provisional list must be protected by the law of that country. In Japan for example, natural assets must be preserved under the Natural Parks Law and cultural assets under the Law for the Protection of Cultural Properties. The organizations responsible for selecting the sites are the Ministry of the Environment, Forestry Agency, Agency for Cultural Affairs, etc.

Currently, a country may recommend up to two sites per year from the provisional list to the UNESCO World Heritage Center.
The conditions of such sites must be favorable in terms of such issues as protective measures and management plans. It is only the government who can conduct recommendations, not individuals or groups. After receiving the letter of recommendation, UNESCO requests a field investigation to an agency specializing in that particular field (ICOMOS [International Council on Monuments and Sites] for cultural assets; IUCN [International Union for Conservation of Nature and Natural Resources] for natural assets) who will conduct the actual research. At this point, it is necessary that the potential sites satisfy one or more of the conditions for registration mentioned in the "'Operational Guidelines for the Implementation of the World Heritage Convention" and that they also fulfill the requirements pertaining to integrity and credibility. Therefore, it is an extremely difficult procedure for sites to be approved as World Heritage Sites.