The Convention concerning the Protection of the World Cultural and Natural Heritage aims to safeguard the cultural and natural heritage of outstanding universal value. World Natural Heritage sites include, for example, unique records of Earth’s history, significant ecological processes, areas of exceptional natural beauty, and endangered habitats. Adopted on 16 November 1972 by the member states of UNESCO, the World Heritage Convention has been ratified by more than 190 countries.

One of the instruments of the Convention is the List of World Heritage in Danger, which identifies properties facing serious threats and requiring special protective measures. The list currently includes around 50 sites and serves as an alert mechanism, drawing international attention to heritage at risk due to factors such as armed conflict, uncontrolled development, environmental degradation, and climate change. Interestingly enough, only three sites have been “lost”, and all due to inappropriate development.

In the following interview, Robert Schäfer and Urška Škerl speak with Dr Mechtild Rössler, former Director of the UNESCO World Heritage Centre, about the evolving role of the World Heritage Convention, the growing pressures on heritage sites and the role of landscape architecture in world-changing paradigms.

What can be achieved with listing World Heritage sites beyond selective protection, especially facing climatic and other threats?

When the World Heritage Convention was drafted in 1972 at the time of the very first United Nations Conference on the Human Environment in Stockholm, the notion of climate change did not exist yet, but people were very aware of threats to the environment, especially air pollution and chemicals – you remember the book ‘Silent Spring’ by Rachel Carson. This is much reflected in the Preamble of the Convention, for example: “in view of the magnitude and gravity of the new dangers threatening them, it is incumbent on the international community as a whole to participate in the protection of the cultural and natural heritage of outstanding universal value…“

While the World Heritage List is a selection of those precious sites on our earth, it constitutes a global monitoring system which identifies key threats and trends. It can, through that, alert other places to prevent disasters, including the rise of sea water in coastal cities, the melting of glaciers and glacial outbursts impacting mountain communities and extreme weather events causing droughts and fires affecting many properties. The Policy on climate action for World Heritage, first prepared 20 years ago in 2007 and now updated in 2023, is a critical document for all, whether the States, site managers or communities. Climate change is the defining threat to the heritage of our times and World Heritage provides a framework for adaptation and mitigation.

You have worked on different programmes with UNESCO for 30 years, also as the Director of the UNESCO World Heritage Centre. The World Heritage List now includes 1248 properties, 972 cultural, 235 natural and 41 mixed – 51 are transnational. Please tell us, how did the attitude towards heritage change over the years, and how is the list of sites growing? 

When I started at UNESCO 35 years ago, the World Heritage List was small, around 300 sites. I never imagined such a fast growth of the list; it became quite popular to nominate sites, often for economic and tourism growth reasons, but also for national prestige and recognition. We have 50% of the sites located in Europe and North America, and that demonstrates that countries with a good protection system, well-developed heritage and research institutions continue to propose nominations. I would like to see a slowing down there to leave the place for underrepresented regions, including sub-Saharan Africa, the Caribbean and the Pacific, as well as underrepresented types of sites.

At UNESCO, we tried to assist with major training initiatives with our advisory bodies ICOMOS, ICCROM and IUCN, for cultural landscapes. Advice is also given with the IFLA-ICOMOS Scientific Committee. Today, the funding, including by the World Heritage Fund, cannot keep pace with the needs of the sites, especially with many conflicts and wars, and increasing threats to heritage such as urban development, climate change and extreme weather events. One of our roles at UNESCO is fundraising for projects at sites in need.

The World Heritage Committee, which is a 21-member committee representing the 196 States Parties of the Convention, has the task of deciding on the inscription of new sites, but more importantly, to review the state of conservation of sites on the World Heritage List. The idea of the Convention is not just to list sites, but to protect and safeguard the heritage places, which is increasingly difficult. So over the years we have developed a comprehensive monitoring system, with reporting, site missions, decisions by the Committee, and if a site is threatened to lose its outstanding universal value, a potential danger listing to alert the international community to help to safeguard the property.

You mention protecting sites endangered by political conflict and the heritage of underprivileged countries. How does UNESCO keep a more complete and balanced image of global heritage?

UNESCO has a network of field offices and monitors the state of conservation regularly with ICOMOS and IUCN. Field missions are carried out, even during conflicts or post-conflict situations. For example, I was the first one with a UNESCO team in April 2016 to enter the Site of Palmyra, an archaeological area and oasis in the Syrian desert, which was attacked by the Islamists (IS) as one of the most important cultural centres of the ancient world. We did a rapid assessment of the damages, visited the museum, which was partially destroyed by a bomb, and its cellar turned into an IS interrogation centre, and evaluated potential reconstruction. Unfortunately, the Islamists came back later and damaged further areas. We work, of course, a lot with new technologies, for example, with UNOSAT/UNITAR satellite images and made a publication to document the situation, which is crucial for the recovery phase for cities such as Aleppo (see the publication Five years of Conflict – The State of Cultural Heritage in the Ancient City of Aleppo) and archaeological sites in Syria. Satellite imagery analysis is now a routine tool for assessing potential damage to cultural heritage sites, but also natural heritage such as the 5 World Heritage sites and national parks in the Democratic Republic of the Congo (DRC).

Sites on the List of World Heritage in Danger, such as in Syria, Iraq, Mali, Yemen, Libya, or DRC are reviewed by the World Heritage Committee at its yearly sessions, and the UNESCO World Heritage Centre prepares the reports together with the advisory bodies. For other sites, we receive reports from States Parties, but often alerts from local communities and NGOs that there are threats, and we check this carefully. Over time, it became a huge monitoring system, with an online „State of conservation Information System“ at UNESCO, where you can find any report or decision taken on a site since its inscription.

What do you do when you lose a site?

If we lose a site, it means that the State concerned, the local authorities, but also the international community, meaning you and me, all of us, did not do enough to protect it. This happened only 3 times in the history of the Convention: the Arabian Oryx Sanctuary (Oman) in 2007 due to an oil and gas development, Dresden Elbe Valley (Germany) in 2009 due to a major bridge construction cutting across this cultural landscape and Liverpool – Maritime Mercantile City (UK) in 2021 due to ill-advised developments along the waterfront. It is very sad to see this, but the delisting was also a wake-up call for many actors and stakeholders that the Convention is a tool for sustainable heritage conservation and not for development at all costs.

These sites are naturally defined by their boundaries. However, there is a general call to look at broader contexts, cultural and urban landscapes, for example, using the terms urban forestry, sponge cities and even sponge planet. What is your view?

I find it important to look at broader contexts, as sites cannot be maintained in isolation. The provisions of the Convention and its Operational Guidelines also require bufferzones and the protection of important views. While the 2011 UNESCO Recommendation on the Historic Urban Landscape came from World Heritage debates on cities, we need to look at the settings, interlinkages between the urban and rural, but also at nature-culture relationships generally. This means to take into account tangible and intangible elements, people and their relations with nature. In this context, urban forestry and sponge cities are not only concepts but a much-needed reality to survive in our more and more urbanised world. Prof. Yu, who just died in the Pantanal, a World Heritage wetland in Brazil, gave an excellent paper at the IFLA World Congress in Nantes in September 2025, to promote the concept of a sponge planet as a paradigm change for our relationship to nature. He will be deeply missed. Our Panel in Nantes discussed ‘territories in transition’, and indeed, we looked into the broader landscape to accompany this process!

In the self-image of landscape architects, a small group represented in 80 countries, they consider their role as important and think they should take the lead in planning. But what can they actually achieve?

While landscape architecture is a relatively new discipline, it has a role to play at the nature-culture, urban-rural, and people-environment interface. With their background, landscape architects can make cities more livable and our planet healthier when they are called into major projects and encourage concepts such as the sponge city. In my town, Freiburg in Southern Germany, there are citizens’ groups such as ‚Freiblocks‘ to promote the ‚Schwammstadt‘ and ‚Superblocks‘ concepts, and they started with small meetings of local communities in different quarters and a landscape design team looking at options for private unsealing of soil (Entsiegelung der Böden) such as asphalt parking spaces. They invited professionals from other cities, such as Zürich (Asphaltknacker) and Barcelona (Superblocks), to analyse together new urban development projects and achievements, including less traffic, more greenery, and improvements in the quality of life of people. Landscape architects can work with others and the communities to make sponge cities a reality. It is critically important to work together with others, including city planners, urban geographers, hydrologists or climate specialists, for long-term changes and at a broader scale for our planet.