- Also spelled:
- Elburz, Albourz, Alburz, or Elburs
- Persian:
- Reshteh-ye KÅ«hhÄ-ye Alborz
Alborz Mountains
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What are the Alborz Mountains?
The Alborz Mountains are a major mountain range in northern Iran, stretching 560 miles (900 km) from the Azerbaijan frontier to the Khorasan region. The range is a defining geographical landmark with cultural significance in Iran.
The Alborz is divided into the Western Alborz, Central Alborz, and Eastern Alborz. The Central Alborz includes Iranās highest peaks, Mount Damavand and Mount Alam. The Caspian slopes of the Alborz have a humid climate that supports dense forests, while the southern slopes share the arid characteristics of the Iranian plateau.
The Alborz contain well-settled districts such as Deylaman, Alamut, Taleqan and Larijan. The mountains have extensive grain cultivation, cattle raising, and alpine pastures. The range also holds economic importance because of its forests, coal mines, dams, and rivers used for irrigation, hydroelectric energy, and water supply.
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Where are the Alborz Mountains located?
The Alborz Mountains are a major mountain range in northern Iran, stretching 560 miles (900 km) from the frontier with Azerbaijan eastward to the Khorasan region. The range runs along the south shore of the Caspian Sea. The Alborz mountain system traverses virtually all of the northernmost portions of Iran from east to west.
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How long is the Alborz mountain range?
The Alborz Mountains, a major mountain range in northern Iran, stretches 560 miles (900 km) eastward in an arc from the frontier with Azerbaijan to the Khorasan region. The westernmost portion is called the Talish Range. The central stretch includes Iranās two highest peaks, Mount Damavand and Mount Alam. The Western Alborz Range runs south-southeastward for 125 miles (200 km), the Central Alborz is 250 miles (400 km) long, and the Eastern, or Shah, Alborz runs about 185 miles (300 km) in a northeasterly direction.
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What is the highest peak in the Alborz Mountains?
The highest peak in the Alborz Mountains is Mount Damavand, an extinct volcano. It is located in the central Alborz range in northern Iran, approximately 42 miles (68 km) northeast of Tehran. Damavand's height ranges from 18,400 feet (5,610 meters) to 18,600 feet (5,670 meters), towering 3,000 to 8,000 feet (900 to 2,450 meters) above the surrounding ranges.
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How do the Alborz Mountains affect the climate in northern Iran?
The Alborz Mountains significantly influence the climate of northern Iran. The mountains trap humidity from northerly air currents that originate over the Caspian Sea, resulting in a humid climate along the Caspian slopes with annual precipitation exceeding 40 inches (1,000 mm) in the Gilan region. This trapped moisture supports lush Hyrcanian forests at lower elevations.
By contrast, the southern slopes of the Alborz Mountains share the arid characteristics of the Iranian plateau, with annual precipitation varying between 11 and 20 inches (280 and 500 mm). The climate on the southern side supports a steppelike vegetation due to the destruction of its original dry juniper forests. The Alborz range also prevents the Caspian Sea's humidity from reaching Tehran, contributing to the hot, arid climate of the city.
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What kinds of plants and animals are found in the Alborz Mountains?
The Alborz Mountains are home to a variety of plant and animal life. The Caspian slopes have a humid climate that supports Hyrcanian forests at the lowest levels, beech forests in the middle zone, and oak forests at higher elevations. Wild cypress can also be found in some sheltered valleys. In contrast, the southern slope shares the arid character of the Iranian plateau and is mostly populated by steppe vegetation.
Although the Hyrcanian tiger is now extinct, other wild cats like leopards and lynx still inhabit the Alborz Mountains. Bears, wild boars, red and roe deer, mouflon (wild mountain sheep), and ibex are also present. Notable birds include eagles and pheasants.
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Alborz Mountains, major mountain range in northern Iran, 560 miles (900 km) long, which serves as a defining landmark both geographically and in Iranian culture. The range, most broadly defined, extends in an arc eastward from the frontier with Azerbaijan southwest of the Caspian Sea to the Khorasan region of northeastern Iran, southeast of the Caspian Sea, where the range merges into the Aladagh, the more southerly of the two principal ranges there. More commonly, however, the westernmost part of the range is called the Talish (Talysh, Talesh, or TavÄlesh) Range, or the Bogrov DÄgh. The Alborz Range, in its strictest sense, forms part of the central stretch of the chain, which also includes Iranās two highest peaks, Mount Damavand and Mount Alam. The Alborz mountain system traverses virtually all of the northernmost portions of Iran from east to west.
Physical features
Geology
The Alborz chain is not as truly alpine (i.e., resembling the European Alps) in its structure as is often suggested. On the one hand, continental conditions regarding sedimentation are reflected by thick Devonian sandstones (about 360 to 415 million years old) and by Jurassic shales containing coal seams (about 145 to 200 million years old). On the other hand, marine conditions are reflected by strata dating to the boundary of the Carboniferous and Permian periods (about 300 million years old) that are composed mainly of limestones, as well as by very thick beds of green volcanic tuffs and lavas. Orogenic (mountain-building) phases of importance date from the Miocene and Pliocene epochs (between about 23 and 2.6 million years ago). Over large areas they produced only a loose folding; but in the Central Alborz a number of folds were formed into blocks thrust mainly southward but in places northward, with cores made of Paleozoic rocks (more than 250 million years old). Structurally and topographically, the Alborz system is less clearly defined on the southern than on the Caspian (northern) side of the chain, since various off-branching elements interconnect it on the southern side with the adjoining Iranian plateau.
Physiography and climate
The Western Alborz Range runs south-southeastward for 125 miles (200 km). Varying in width from 15 to 20 miles (24 to 32 km), it consists of a single asymmetric ridge, the long slope facing the Caspian. Few of its peaks approach or exceed 10,000 feet (3,000 meters) in height. There is a low pass west of Astara, near the Azerbaijan frontier, 5,000 feet (1,500 m) above sea level. The Sefid River, formed by the junction of the Qezel Owzan (Qisil Uzun) and Shahrud rivers, is the only river to cross the whole width of the chain: its gorge, giving access to the low pass of Qazvin, offers the best passage through the mountain chain, although by no means an easy one, between the Gilan region on the shores of the Caspian and the inland plateau to the south.
The Central Alborz is 250 miles (400 km) long. East of the longitude of Tehran, which lies to the south of the range, it reaches a width of 75 miles (120 km). Located among the longitudinal valleys and ridges of the range are some important centers of settlement, with the towns of Deylaman, Razan, Kojur, and Namar located on the Caspian side and Shahrud, Lar, Damavand, and Firuzkuh on the southern side. There are likewise many gorges, by which the rivers find their way down one or another of the slopes. Only two passes allow a relatively easy crossing in a single ascentāthose are the Kandovan Pass, between the Karaj and the Chalus rivers, and the Gaduk Pass, between the Hableh and the Tala rivers. The main divide runs generally south of the highest crest, whichāwith the exception of the towering and isolated cone of the extinct volcano Mount Damavand (18,386 feet [5,604 meters])āculminates in the glaciated massif of Takht-e Soleyman, which rises to more than 15,750 feet (4,800 meters).
The Eastern, or Shah, Alborz runs about 185 miles (300 km) in a northeasterly direction. Since two ranges branch off on its southern side and no compensatory elements appear on the northern side, its width dwindles to less than 30 miles (48 km). With the exception of the Shah Range proper (which reaches an elevation of 12,359 feet [3,767 meters]), the chain decreases in height toward the east. Longitudinal valleys are found less and less frequently east of the Shah. There are several passes at low elevations.
The Caspian and the inland, or southern, slopes of the Alborz differ markedly from each other in climatic and vegetational aspects. The Caspian slope has a distinctly humid climate, thanks to northerly air movements, enriched with moisture from the sea, which collide with the steep faces of the mountains to cause precipitation. The precipitation amounts to more than 40 inches (1,000 mm) annually in the lowlands of the Gilan region and is even more plentiful at higher elevations. Although it decreases toward the east, it still suffices to nourish a humid forest for the whole length of the chain on the Caspian side, where the soils are mostly of the brown-forest type. The natural vegetation of that slope grows in distinct zones: the luxuriant Hyrcanian forest on the lowest levels; a beech forest in the middle zone; and a magnificent oak forest from the elevation of 5,500 feet (1,700 meters) up to the levels where gaps in the divide allow the moist air to overflow into the inland basins. In some sheltered valleys there are extensive stands of wild cypress. Sheltered valleys adjacent to the Sefid River constitute the only olive-growing areas of note in Iran.
The southern slope of the Alborz, by direct contrast, shares the arid character of the Iranian plateau. Annual precipitation varies between 11 and 20 inches (280 and 500 mm) and is very irregular. The soils are mostly of the type associated with steppe (treeless, grassy, or shrubby) vegetation. The slope has become even more steppelike ever since the almost complete destruction of its original dry forest of junipers.
Animal life
The Hyrcanian tigers for which the Caspian forests were famous are now extinct, but other wild cats, such as the leopard and the lynx, are still numerous in the Alborz. The bear, the wild boar, red and roe deer, the mouflon (wild mountain sheep), and the ibex are also present. Eagles and pheasants are notable among birds.
Settlement and economy
Although large areas of the Alborz Mountains are almost uninhabitedāsome being occupied only by nomads and others having been depleted by Turkmen raids in the 19th centuryāthere are still several well-settled districts, including Deylaman, Alamut, Taleqan, and Larijan (at the foot of Mount Damavand). The landscape of the Caspian slopes is characterized by forest clearings with shingle-roofed loghouse villages and by lush fields and pastures. The landscape of the inland slopes is of the oasis type. Extensive grain cultivation occurs on both slopes, and cattle raising occurs on the Caspian side. Alpine pastures, seasonally dotted with flocks of sheep, cover an extensive zone yet higher. The land-distribution pattern prevailing in the Alborz includes a high proportion of small land ownership. The holdings often are much-fragmented.
Many of the traditional ways of livelihood of the mountaineers, including charcoal burning (now prohibited because of devastation of the forests), the transportation of goods (especially of rice and of charcoal for Tehran) by pack animals, and the working of hundreds of small coal mines, were displaced by the 20th-century modernization of Iran.
Apart from the main line of the trans-Iranian railroad, which links Tehran with Bandar-e Torkeman via the Gaduk Pass, there are several asphalted roads across parts of the Alborz. From west to east, those run between Ardabil and Astara, between Qazvin and Rasht, between Tehran and Chalus, between Tehran and Amol (via Damavand); between Tehran and Babol (via Firuzkuh), and between Shahrud and Gorgan (via Kotal-e ZardÄneh Pass).
The wild (natural or original) forests of the Alborz Mountains cover more than 8,000,000 acres (3,000,000 hectares), of which some 3,000,000 acres can be exploited commercially for timber and other wood. There are also a few modern coal mines, as well as some deposits of iron and other ores. But most important is the water of the rivers, which is used for irrigation, for generating hydroelectric energy, and for supplying the fast-growing Tehran. Spectacular dams have been built. Those include the Sefid RÅ«d Dam, used for the irrigation of the Sefid river delta; the Karaj Dam and the Jajrud Dam, used mainly for supplying water to Tehran and partly for irrigation; and a series of dams on other rivers of the Mazandaran ostÄn (province) also used for irrigation.
