Dena with 80 kilometers length is the longest mountains of Zagros and world’s famous mountaineers have named these mountains Alps in Iran.
Dena is a mountainous area with steep slope and low snow, evaporation and transpiration and high flooding potential. Dena is the sequence of Zagros Mountains.
Dena has 49 summits higher than 4000 meters.
Mountains with general slope of more than 60 percent and height difference of more than 500 meters from 3100 up to 4287 meters contains about 89 percent of the protected area of Dena.
Gahshmastan peak (Bijan 3) with the height of 4435 meters is the highest point in the region.
The lowest point is 1359.2 meters in height in North West.
This region is a totally mountainous area with cliffs, headlands and impassable heights and despite a set of foothills, it has the highest point of 4425 meters with the height difference of 3000 meters between the highest and the lowest parts.
The protected area Dena is invaluable in terms of plant species and it is considered a valuable genetic capital considering the trees, forest, and pasture plants, medicinal, edible and decorative plants. The wildlife of this area represents the biodiversity of fauna in Zagros Mountains.
The protected area Dena was known as biosphere reserves in 1389 with the consent of Supreme Council of UNESCO. Before registration of Dena in Kohgiloyeh and Boyerahmad, 9 national park reserves of Uremia, Golestan, Kavir, the protected areas of Arasbaran in eastern Azerbijan, Touran in Fars Province, Genu and Hara in Hormozgan, Arjan and Parishan in Fars Province and Miankaleh wildlife shelter in Mazandaran Province were registered in the list of biosphere reserves of Iran in UNESCO.