It's true that we've only seen dinosaurs in movies, but with just a few hour drive from Tehran, one can be in forests that are just as old as dinosaurs. Located in the south of the Caspian Sea, from Mazandaran to Gilan, from Gorgan to Arasbaran, there are Hyrcanian forests, forests that are of great value and have been registered by UNESCO.
Hyrcanian forests of Iran so-called "Northern Forests" form the most dense forest area of this country. Located in the south of the Caspian Sea, these forests are shared between Iran and Azerbaijan. Hyrcanian forests have been there from 40 million years ago.

Where are the Hyrcanian forests?

From the Hyrcania ancient region in the Republic of Azerbaijan to Astara, the border Iranaian city there are spectacular old forests that enjoy temperate climate of the region. This eco-region continues along the south coast line of the Caspian Sea and the northern slopes of the Alborz Mountain range. It covers parts of five provinces of Iran from east to west including: North Khorasan Province, Golestan Province (entirely southern and southwestern areas as well as parts of the eastern regions of the Gorgan plain, Mazandaran Province, Gilan Province and Ardabil Province.
The area of these 40 million year old forests is 55,100 square km with 2 million hectares in Iran and 20,000 hectares in Azerbaijan. Its height starts from the sea level and reaches 2800 meters above the sea level. Unfortunately, almost half of these forests are now deforested, and only 10.3% of them is heavily protected.
Hyrcanian forest ecosystems are home to 296 bird species and 98 mammal species. There are also 150 native plants including trees and shrub plants such as buxes and beech trees.

Causes of Hyrcanian Deforestation 

Although Iran is a poor country in terms of vegetation, we still witness a huge decline in the Hyrcanian eco-region each year.
One of the main causes of this destruction is the unrestrained expansion of the wood and paper industries and the changing use of these forests. Another major destructive factor is construction projects, such as the construction of dams without sufficient research. Golwerd Dam in Mazandaran province is an example, where more than thirty thousand trees were cut in the project. Other factors include uncontrolled grazing domestic livestock and illegal constructions. Also in the not too distant past, millions of cubic meters of wood were used in Coal industries, which fortunately has been neglected today. 

Hyrcanian Forests Flora

These forests mostly consist of broad-leafed species that are adapted to the humid, semi-Mediterranean climate. Hyrcanian forests often have different vegetation depending on the altitude (sea level, low altitudes mountain foot, high mountains, and very high places). The most famous of these trees are Beech, Oak, Alder, Elm, European Ash, Box-tree, etc. Categorized as Deciduous broad-leafed Trees, in total, there exist 150 species of trees and shrubs in the Caspian eco-region. The tree types in the lowland area also differ from the trees in the high slopes and areas.

Categorized as Deciduous broad-leafed Trees, in total, there exist 150 species of trees and shrubs in the Caspian eco-region. The tree types in the lowland area also differ from the trees in the high slopes and areas.
Beech, Oak, Maple, Elm, Alder, European Ash, European Hornbeam, Yew, Lindens, Parrotia persica, Caucasian wingnut, Lilac, Date-plum, Fig and Box-trees are more abundant than others.

Hyrcanian Forest UNESCO World Heritage List

The age of these forests and the inadequacy and the type of its plants prompted applies and requests for UNESCO World Heritage Registration. At first the Republic of Azerbaijan made this request, but since most of the forests were located in Iran, Iran proposed a joint request with Azerbaijan, and the request was submitted to UNESCO and registered.