What is a World Heritage Site?

Some places are so special that the whole world wants to keep them safe.

They are called World Heritage Sites. They can be old buildings, ancient cities, forests, reefs or islands.

Heritage is what we receive from the past, live with today and pass on to people in the future. Some heritage is cultural, made by people, like a palace or an ancient city. Some is natural, like a coral reef or a mountain range.

In 1972, countries meeting at UNESCO, the United Nations organization for education, science and culture, agreed to work together to protect the world's most important places. Places chosen under this agreement are called World Heritage Sites. Each one stays in its own country, which looks after it, but all the countries that signed promise to help protect them.

UNESCO describes heritage as our legacy from the past, what we live with today and what we pass on to future generations, and calls cultural and natural heritage irreplaceable sources of life and inspiration. The Convention concerning the Protection of the World Cultural and Natural Heritage was adopted by UNESCO's General Conference in Paris on November 16, 1972.

Its key idea is Outstanding Universal Value: some places matter so much that their protection concerns all humanity. Only countries that have signed the Convention, called States Parties, can nominate sites on their territory, and they pledge to protect their heritage. In 2026, 196 States Parties had signed, and 173 of them had at least one property on the list.

Choosing a World Heritage Site takes a long time.

First, a country makes a list of its special places. Then experts visit and check. Then a big committee decides.

Becoming a World Heritage Site takes years. First, a country puts the place on its Tentative List, a list of the places it might nominate in the next five to ten years. Next, it prepares a big report, called a nomination file, explaining why the place is special.

Then experts check it. ICOMOS, a group of experts on monuments and sites, checks cultural places, and IUCN, the International Union for Conservation of Nature, checks natural ones. They visit the site over about 14 months. Finally, the World Heritage Committee, which meets once a year, decides whether to add the place to the list.

UNESCO sets out four steps. (1) Tentative List: a State Party's inventory of significant heritage it may nominate within five to ten years; a site must be on it before the Committee can examine a nomination. (2) Nomination file: a mandatory desk-based Preliminary Assessment, in which the Advisory Bodies advise whether the site could justify Outstanding Universal Value, then a full dossier due by February 1 for a completeness check.

(3) Evaluation: over 14 months, ICOMOS (the International Council on Monuments and Sites) evaluates cultural nominations and IUCN natural ones, including a mission to the site, an interim report and requests for information. (4) Decision: the intergovernmental World Heritage Committee, meeting once a year, may inscribe, defer, refer or decline. To be inscribed, a site must show Outstanding Universal Value and meet at least one of ten criteria.

A World Heritage Site must be special in at least one way.

It might be a wonderful building. It might show how people lived long ago. Or it might be a beautiful wild place with rare animals.

UNESCO has ten criteria, or tests, and a place must pass at least one. Six are about culture: for example, being a masterpiece of human creative genius, or being an outstanding example of a type of building or of a traditional way of living on the land or sea.

Four are about nature: having superlative natural features or exceptional natural beauty, showing major stages of Earth's history, showing important ecological processes, or holding the most important habitats for protecting wildlife, including threatened species.

Until the end of 2004 sites were judged against six cultural and four natural criteria; the revised Operational Guidelines merged them into one set of ten. Criteria (i) to (vi) cover masterpieces of human creative genius, interchanges of human values, testimony to a cultural tradition or civilization, outstanding types of building or landscape, traditional settlement or land- and sea-use, and association with events, traditions, ideas or beliefs of outstanding universal significance.

Criteria (vii) to (x) cover superlative natural phenomena or exceptional natural beauty; major stages of Earth's history, including the record of life and geological processes; significant ongoing ecological and biological processes; and the most important natural habitats for in-situ conservation of biological diversity. The Committee revises the criteria regularly to reflect how the World Heritage idea itself evolves.

Some special places are in trouble.

They might be harmed by too many buildings, pollution or storms. A special list helps the world notice and help.

Being on the list does not make a place safe by itself. UNESCO warns that sites can be harmed by uncontrolled building, too much tourism, neglect, natural disasters, pollution, political instability and conflict.

When a site's special qualities are threatened, it can be put on the List of World Heritage in Danger. This tells the whole world that the site needs help and encourages action to fix the problems. In 2026, 58 sites were on this list. By 2026, 3 sites had even been removed from the World Heritage List.

UNESCO lists the pressures on sites as uncontrolled urban development, unsustainable tourism, neglect, natural calamities, pollution, political instability and conflict. The List of World Heritage in Danger is designed to inform the international community of conditions threatening the very characteristics for which a property was inscribed and to encourage corrective action; UNESCO now encourages telling its story in terms of positive conservation efforts rather than negativity.

In 2026, 58 properties were on the List in Danger, and 3 had been delisted. The Convention itself frames protection as shared: while fully respecting the sovereignty of the country where a site lies, States Parties recognize it as a world heritage that the international community as a whole has a duty to cooperate in protecting, and each undertakes not to take deliberate measures that might damage heritage in other States Parties.