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Hyrcanian Forests (Iran (Islamic Republic of))

Date of Submission: 30/09/2020
Criteria: (ix)(x)
Category: Natural
Submitted by:
Iranian Ministry of Cultural Heritage Tourism and Handicrafts
State, Province or Region:
Eastern Azarbaijan province of Islamic Republic of Iran
Coordinates: N38 40 37 - N38 58 11 and E46 17 30 - 46 44 25
Ref.: 6489
Other States Parties participating

The Tentative Lists of States Parties are published by the World Heritage Centre at its website and/or in working documents in order to ensure transparency, access to information and to facilitate harmonization of Tentative Lists at regional and thematic levels.

The sole responsibility for the content of each Tentative List lies with the State Party concerned. The publication of the Tentative Lists does not imply the expression of any opinion whatsoever of the World Heritage Committee or of the World Heritage Centre or of the Secretariat of UNESCO concerning the legal status of any country, territory, city or area or of its boundaries.

Property names are listed in the language in which they have been submitted by the State Party


The Hyrcanian Forests form a green arc of deciduous mixed broad-leaved forests stretching across some 850 kilometres along the Caspian Sea, from the Talish Mountains in the Republic of Azerbaijan across the Alborz Mountains all the way to Golestan Province in the Islamic Republic of Iran. As the main climatic barrier and watershed between the Caspian Sea and the arid Irano-Turanian Plateau, the steep ridges of the Talish and Alborz mountain systems serve as an insuperable barrier of moist air accumulated above the Caspian Sea. As a result, there is ample precipitation feeding many rivers and creeks rapidly flowing down steep slopes and mountain gorges into the Caspian Sea. Thus, the Hyrcanian Forests (sometimes also referred as “Caspian Forests”), are metaphorically squeezed in between the “claws” of the Caspian Sea and arid drylands.

The forests are geographically separated and biogeographically distinct from Caucasus mountain forests, but linked with the latter by transition types found in Dizmar Protected Area (Iran). Due to highly particular topographic and climatic conditions, the Hyrcanian Forests survived the ice age periods as extremely rare “Tertiary relict forests” and have subsequently been adapting to the postglacial climate changes. Their natural distribution area is limited by the Caspian Sea, and by two main ecotones: first, the altitudinal treeline in the mountains and the dryness treeline where the forests transition into the mountain grasslands and semi-deserts of the South-Caucasian and Irano-Turanian dryland regions.

The serial World Heritage nomination of carefully selected representations of the Hyrcanian Forests located in the Islamic Republic of Iran was inscribed on the occasion of the 43rd session of World Heritage Committee in Baku, Azerbaijan, according to criterion (ix) (Decision 43 COM 8B.4). The serial property encompasses 15 component parts representing key examples of the various stages and features of natural Hyrcanian forest ecosystems. While most of the ecological particularities characterizing the Hyrcanian Forests are represented in the inscribed property, there is considerable potential for further serial extension to include additional areas of global conservation value in both the Islamic Republic of Iran and the Republic of Azerbaijan. The proposed serial transnational extension amounts to a full nomination, triggering a prior updating of the Tentative Lists of both involved States Parties. The additional components proposed are described below. All add value to the inscribed property in terms of inscription criteria (ix) and (x). It deserves to be emphasized that the Committee explicitly encouraged a transnational approach (see Decisions 30 COM 8B.24 and 43 COM 8B.4).

The forest region is recognized as a Tertiary floristic center, representing a vast natural museum featuring numerous endemic and relic species. Jointly with the Colchis of Georgia, it is the most important arcto-tertiary relic and diversity center of broad-leaved deciduous forest vegetation (nemoral forest biome) and its flora and fauna in Western Eurasia, stretching from the coastal lowlands and foothills to the upper mountain belt. Despite the similarities,there are important differences between Colchic and Hyrcanian forests in terms of climate, forest structure and composition as well as altitudinal zoning. For example, the upper mountainous forest belt in the Colchis is formed by evergreen coniferous forests of Abies nordmanniana and Picea orientalis, whereas deciduous broad-leaved forests of Quercus macranthera and Carpinus orientalis dominate this altitudinal belt in the Hyrcanian region. The most characteristic and specific relic tree species of the Hyrcanian forests, Parrotia persica, is entirely missing in the Colchis. While nemoral broad-leaved forests also occur in Europe, Eastern Asia and North America, they have mostly been converted to agricultural land or fundamentally altered and degraded by human activities there. Unlike anywhere else at this scale, the Tertiary flora continues to be exceptionally intact, both in the inscribed property and the components proposed as extensions. The most intact representations of the Hyrcanian Forests can thus be regarded as the best available representation of intact Holarctic mixed and deciduous forests worldwide.

Name(s) of the component part(s)

Dizmar (Two parts of Dizmar Protected Area were selected for their values and intactness)

Description of the component part(s)

Dizmar Protected Area, as a part of the Iranian Highlands, is a transition type of the mountainousHyrcanian forestsalong steep and rugged slopes located at the meeting point of three different phytogeographical regions, in the northwest of Iran. The total area of Dizmar Protected Area is about 70000 ha which two component parts (Dizmar1 and Dizmar2) were selected with total area of about 6000 ha. As proposed property. The area is restricted to the border river Aras in the north and the mountain areas in the east, west and south, and is connected to Kiyamaki Protected Area, Arasbaran Biosphere reserve. Moisture from the Caspian Seain the east, the Mediterranean Sea in the west and Siberian low-pressure fronts from the north, result in an annual precipitation of around 300-600 mm, foggy conditionsas hidden precipitation which permit ancient and lush deciduous broadleaved forests, extending from some 400to around 2,600 m a.s.l. The co-existence of different phytogeographical and floristic elements in addition to endemic plant species, lead to an exceptionally complex vegetation structure.

Despite occupying a small area only, remarkable biodiversity with rich flora (about 849 recorded plant species) and fauna (morethan 320 vertebrate species) and a high degree of endemism (76 plant species). The presence of the rare bird endemic species such as Lyrurus mlokosiewiczi (Near Threat species in IUCN category) led to the designation as a protected area in 2011. The area serves as key habitat for numerous threatened species. It is home to some spectacular species of large mammalian predators, including the Persian leopard (Panthera pardus saxicolor), Brown bear (Ursus arctos), Wild goat (Capra aegagrus VU),Striped Hyaena (Hyaena hyaena NT), Caracal (Caracal caracal) and the wild cat (Felis silvestris).A wildlife conservation corridor, it functions as a major corridor in the Caucasian region for mammals and migratory birds flying between Northern breeding grounds and southern wintering grounds.

Justification of Outstanding Universal Value

Selected parts of the Hyrcanian Forests located in the Islamic Republic of Iran were inscribed on the World Heritage List in 2019 under criterion (ix). The proposed transnational serial extension is based on criteria (ix) and (x). 

The serial property contains exceptional and ancient broad-leaved forests, which retreated during periods of glaciation and later expanded again under milder climatic conditions. Due to this isolation, the serial property hosts many relict, endangered, and regionally and locally endemic species of flora, contributing to the high ecological value of the property and the Hyrcanian region in general.

Criterion (ix): The existing property brings together a carefully selected series of intact representations of the Hyrcanian forest ecosystems. Its component parts contain exceptional broad-leaved forests with a history dating back 25 -50 million years ago, when such forests covered most of the Northern Temperate Region. These huge ancient forest areas retreated during Quaternary glaciations and later, during milder climate periods, expanded again from these refugia. The property covers most ecological and biological features values of the Hyrcanian region, thereby displaying key environmental processes illustrating the genesis of these forests, including succession, evolution and speciation. Additionally, proposed component parts will further enhance the completeness and integrity of the property and to conserve these remarkable forests located in the territory of two States Parties.

Criterion (x): The Hyrcanian forests are home to globally significant plant and animal diversity. Because of the uninterrupted and ongoing evolution, the floristic biodiversity of the Hyrcanian region is highly remarkable for a temperate forest ecosystem at the global level with over 3,200 vascular plants documented. Due to its isolation, the property hosts populations of many relict, endangered, and regionally and locally endemic plant species, contributing to the ecological significance of the forests, and the Hyrcanian region in general. About 300 taxa are endemic and sub-endemic for the Hyrcanian region, and many plant species are endemic for Azerbaijan and/or Iran. The most conspicuous “living fossils” include tree species like the Persian Ironwood (Parrotia persica), a monotypic endemic tree genus, Caucasian Wingnut (Pterocarya fraxinifolia) and Caucasian Elm (Zelkova carpinifolia).

The ancient forests display all phases of natural regeneration cycles at a large scale. As a result, the intact parts of the Hyrcanian Forests continue to harbour all of the features of natural temperate broad-leaved forests, many of which are missing in degraded and/or managed forests. These features include a high share of ancient trees which offer habitat for an enormous array of life forms. The same holds true for the massive quantities of standing deadwood and coarse woody debris on the ground. For this reason, the Hyrcanian Forests offer, for example, habitat for an extraordinary number of highly specialized and endemic saproxylic beetles (Coleoptera). The presence of numerous so-called “Urwald relic species” illustrates the unusually high level of integrity. Charismatic large mammals include, for example, the main populations of the endangered Persian Leopard (Panthera pardus saxicolor), two other cat species (Lynx lynx, Felis chaus), Wild Goat (Capra aegagrus), Wild Sheep (Ovis ammon arkal). Impressive 18 bat species indicate both intact habitat and a great amount of insects within the forest ecosystem. Many of the reptiles and amphibians occurring in the Hyrcanian Forests are endangered or near threatened according to the IUCN Red List.

Statements of authenticity and/or integrity

The component parts of the inscribed property are functionally linked through the shared evolutionary history of the Hyrcanian mixed forest ecoregion and there are no major barriers to the ecological connectivity in higher elevations of the Hyrcanian forest region. While the lowland forests near the Caspian Sea have been subject to major conversion and degradation, most of the selected components continue to be embedded in a much larger forest landscape, which continues to constitute a vast and almost uninterrupted forest. All inscribed component parts have been selected based on careful analysis of conservation values, representativeness and integrity. The same approach will be applied to the intended serial extension.

Both the inscribed component parts and the ones additionally proposed through a transnational serial extension therefore represent the most intact representations of the various forest sub-types of the vast forest region. The high degree of naturalness is in most cases a function of natural protection due to remoteness and rugged terrain and explicit conservation efforts. Unlike most comparable temperate forests in the northern hemisphere, the selected forests show all the elements characterizing ancient natural forests with very limited human impacts. These characteristics include very old trees, presence of all temporal phases of natural forest regeneration cycles in a spatial mosaic, large amounts of standing dead trees (snags) and coarse woody debris on the ground. Accordingly, the full spectrum of species depending on such characteristics is present, the extinct Caspian tiger being the only species missing in the natural mammalian species assemblage. Jointly, the inscribed components constitute a meaningful and representative portion of one of the world’s most remarkable forest regions. The additional components are intact representations of the enormous diversity of the Hyrcanian Forests not yet represented, including the important forest transition found in parts of new introduced component parts.

Justification of the selection of the component part(s) in relation to the future nomination as a whole

Dizmar, as a part of the Hyrcanian region, which Represent the western transtion of the Hyrcanian forests and with Conservation of a larger area with endemic and threatened species adds to the diversity of the Hyrcanian forest composition has distinct floristic, ecological and wild-life characteristics and is the key habitat for several rare species. The proposed area is a globally outstanding example of the evolution of temperate forests, the survival of fossil tree species, as well as of the ongoing ecological processes of diversification and adaptation to constantly changing environmental conditions. Despite the limited area, presence of 849 plant species and 320 vertebrate species along with the high degree of endemism. Brown bear, leopard, Eurasian lynx, wild goat, wild sheep, Caspian snow cock, snow cock and pheasant are among the most important wildlife species. Dizmar as a part of two biodiversity hotspots (Irano-Anatolian hotspot and Caucasus hotspot) is also a major wildlife conservation corridor for mammals and migratory birds.

Comparison with other similar properties

The nomination dossier of the inscribed Hyrcanian Forests property contains a detailed comparative analysis, which remains fully applicable to the proposed transnational serial extension. Key information is summarized hereafter:

Of the roughly 110 properties, which can be referred to as “Forest World Heritage sites”, temperate forests are an underrepresented category for the simple reason that those forests have disproportionately suffered from forest loss and degradation. Most of the comparable forests have disappeared or are in a state of conservation, which does not permit World Heritage consideration. While the lowland forests along the Caspian shore for the most part share the fate the world’s temperate forests elsewhere, the more remote locations of the Hyrcanian Forests are a rare exception to the global pattern.

Due to fundamental ecological differences, a comparison with sub-arctic, boreal, tropical and sub-tropical forests is considered unhelpful. Compared to the (mixed) and deciduous broad-leaved forests of the world, it was also considered unhelpful to engage in comparison with the likewise very distinct temperate forests of the southern hemisphere. The most relevant comparisons thus have to be made with (mixed) and deciduous broad-leaved forests in the northern hemisphere, also referred to as nemoral deciduous forest regions. As noted, not many large and intact remnants of such forests exist. Where they exist, they have attracted major conservation attention, which has in some case resulted in the establishment of protected areas. The Hyrcanian Forests stand out within the relatively small number of meaningful remnants of nemoral deciduous forests due to their unique isolated location between the Caspian Sea, high mountains and non-forested drylands. In terms of the sheer age and duration of evolutionary processes, the Hyrcanian Forests can only be compared to the forests of the Colchis. However, the latter differ substantially in terms of species composition and structure. Both the scale of the overall forest ecosystem and the intactness of representations along enormous altitudinal and longitudinal gradients are unmatched.

As the full comparative analysis in the nomination dossier for the inscribed property concludes, there are “no comparable World Heritage Forest Sites globally with similar values inscribed on the World Heritage List” and, within the deciduous broad-leaved forest biome worldwide, there are “no properties with a comparable combination of values and attributes (...). It deserves to be noted that the comparative analysis for the existing property identified Hirkan National Park in Azerbaijan as a protected area containing “the potential areas for a possible future serial extension”. Parts of the western extreme of Hyrcanian Forests in Iran, specifically Dizmar Protected Area, have also been identified as possible future components, which can be biologically and ecologically linked to the Hyrcanian Forests.