The unique Caspian Hyrcanian mixed forests with an area and length of about 55,000 km2 (seven percent of Iran’s area) and 850 km are located along the southern coast of the Caspian Sea, covering parts of five provinces (North Khorasan, Golestan, Mazandaran, Gilan, and Ardebil). The history of these forests dates back to 25 to 50 million years ago during the Quaternary glaciations era. Hyrcania refers to the old name of Gorgan city in Greek language, known as Jorjan or Vorkan as well and “Vorkan” according to the inscriptions remained from Achaemenid era. Due to its various endemic flora and fauna, these forests were inscribed by UNESCO as a World Heritage Site in Baku on July 2019, introducing them as the country’s 24th site and the second natural site.
The plant biodiversity of this ecoregion with mountains ranging from low to high altitudes and 3200 species consists of 44 percent of the vascular plants that are found in Iran. For example, 150 endemic tree and bush species such as Parrotia, Buxus, Taxus baccata and Juniper can be found in these forests. In terms of fauna, these forests are habitat of 180 species of birds and 58 species of mammals such as Cervus elaphus, Persian fallow deer, Panthera pardus tulliana, brown bear, and wolf. The government of Islamic Republic of Iran and United Nations Development Program have started a common five-year project to protect biodiversity of these forests