(ii.) The Caucasus range runs from north-west to south-east from the Strait of Kerch to the Caspian Sea for a length of 900 m., with a varying breadth of 30 to 140 m., and covers a surface of 12,000 sq. m. The orographical characteristics of the Caucasus are described in detail under that heading.

(iii.) The combined valleys of the Rion and the Kura, which intervene between the Caucasus and the Armenian highlands, and stretch their axes north-west and south-east respectively, embrace the most populous and most fertile parts of Caucasia. They correspond roughly with the governments of Kutais, Tiflis, Elisavetpol and Baku, and have a population of nearly 3,650,000. The two valleys are separated by the low ridge of the Suram or Meskes mountains.

Spurs from the Caucasus and from the Armenian highlands fill up the broad latitudinal depression between them. Above (i.e. west of) Tiflis these spurs so far intrude into the valley that it is reduced to a narrow strip in breadth. But below that city it suddenly widens out, and the width gradually increases through the stretch of 350 m. to the Caspian, until in the Mugan steppe along that sea it measures 100 m. in width. The snow-clad peaks of the main Caucasus, descending by short, steep slopes, fringe the valley on the north, while an abrupt escarpment, having the characteristics of a border ridge of the Armenian highlands, fronts it on the south. The floor of the valley slopes gently eastwards, from 1200 ft. at Tiflis to 500 ft. in the middle, and to 85 ft. below normal sea-level beside the Caspian. But the uniformity of the slope is interrupted by a plateau (2000-3000 ft. in altitude) along the southern foothills of the east central Caucasus, in the region known as Kakhetia, drained by the Alazan, a left-hand tributary of the Kura. The deep, short gorges and glens which seam the southern slopes of the Caucasus are inhabited by Ossetes, Tushes, Pshavs and Khevsurs in the west, and by various tribes of Lesghians in the east. In these high and stony valleys every available patch of ground is utilized for the cultivation of barley, even up to altitudes of 7000 and 8000 ft. above the level of the sea; but cattle-breeding is the principal resource of the mountaineers, whose little communities are often separated from one another by passes, few of which are lower than 10,000 ft. The steppes along the bottom of the principal valley are for the most part too dry to be cultivated without irrigation. It is only in Kakhetia, where numerous mountain streams supply the fields and gardens of the plateau of Alazan, that wheat, millet and maize are grown, and orchards, vineyards and mulberry plantations are possible. Lower down the valley cattle-breeding is the chief source of wealth, while in the small towns and villages of the former Georgian kingdom various petty trades, exhibiting a high development of artistic taste and technical skill, are widely diffused. The slopes of the Armenian highlands are clothed with fine forests, and the vine is grown at their base, while on the wide-stretching steppes the Turko-Tatars pasture cattle, horses and sheep. The lower part of the Kura valley assumes the character of a dry steppe, the rainfall not reaching 14 in. annually at Baku, and it is still less in the Mugan steppe, though quite abundant in the adjacent region of Lenkoran. The vegetation of the steppe is on the whole scanty. Trees are generally absent, except for thickets of poplars, dwarf oaks and tamarisks along the course of the Kura, the delta of which is smothered under a jungle of reeds and rushes. The Mugan steppe is, however, in spite of its dryness, a more fertile region in virtue of the irrigation practised; but the Kura has excavated its bed too deeply to admit of that being done along its course. The Lenkoran district, sometimes called Talysh, on the western side of the Kizil-Agach bay, is blessed with a rich vegetation, a fertile soil, and a moist climate.

The inhabitants of the Kura valley consist principally of Iranian Tates and Talyshes, of Armenians and Lesghians, with Russians, Jews and Arabs. This conjoint valley of the Rion-Kura was in remote antiquity the site of several Greek colonial settlements, later the seat of successive kingdoms of the Georgians, and for centuries it has formed a bulwark against hostile invasions from the south and east. It is still inhabited chiefly by Georgian tribes—Gurians, Imeretians, Mingrelians, Svanetians—in the basin of the Rion, and by Georgians intermingled with Armenians in the valley of the Kura, while the steppes that stretch away from the lower course of the latter river are ranged over by Turko-Tatars. Mingrelia and Imeretia (valley of Rion) are the gardens of Caucasia, but the high valleys of Svanetia, farther north on the south slopes of the Caucasus mountains, are wild and difficult of access. In the cultivated parts the land is so exceedingly fertile and productive that it sells for almost fabulous prices, and its value is still further enhanced by the discovery of manganese and copper mines in the basin of the Rion, and of the almost inexhaustible supplies of naphtha and petroleum at Baku in the Apsheron peninsula. The principal products of the soil are mentioned lower down, while the general character of the vegetation is indicated under Caucasus: Western Caucasus. In the basin of the Rion, in that of the Chorokh (which runs off the Pontic highlands into the Black Sea south of Batura), and on the Black Sea littoral from Batum northwards to Sukhum-kaleh, and beyond, the climate is extremely hot and the rainfall heavy (see under Climate below). It is in this valley that the principal towns (except Vladikavkaz at the north foot of the Caucasus) of Caucasia are situated, namely, Baku (179,133 inhabitants in 1900), Tiflis (160,645 in 1897), Kutais (32,492), and the two Black Sea ports of Batum (28,512) and Poti (7666).

(iv.) The highlands of Armenia are sometimes designated the Minor Caucasus, Little Caucasus and Anti-Caucasus. But to use such terms for what is not only an independent, but also an older, orographical formation than the Caucasus tends to perpetuate confusion in geographical nomenclature. The Armenian highlands, which run generally parallel to the Caucasus, though at much lower elevations (5000-6000 ft.), are a plateau region, sometimes quite flat, sometimes gently undulating, clothed with luxuriant meadows and mostly cultivable. From it rise double or triple ranges connected by cross-ridges and spined with outer spurs. These double and triple ranges, which have a general elevation of 8500-10,000 ft., stretch from the south-east angle of the Black Sea, 400 m. south-eastwards to the Kara-dagh and Salavat mountains in north Persia, and the latter link them on to the Elburz mountains that skirt the southern end of the Caspian Sea. Various names are given to the different parts of the constituent ranges, or, perhaps more correctly, elongated groups of mountains. The Ajar, Akhalt-sikh and Meskes or Trialety groups in the west are succeeded farther east by the Somkhet, Murguz, Ganji and Karabakh sections, forming the southern rim of the Kura basin, while parallel with them, but farther south, run the Mokry, Miskhan, Akmangan and Paltapin ranges, marking the northern edge of the Aras drainage area. These two sets of parallel ranges are linked together transversely by the cross-ridges of Bezobdal, Pambak, Shah-dagh and Gok-cha. From this last branches off the highest range in the entire series, namely, the Zangezur, which soars up to 10,000 ft. above the left bank of the Aras. From it again there shoot away at right angles, one on each side, the ranges of the Dar-alagöz and Bergushet. These highlands exhibit very considerable evidences of volcanic activity both in remote geological periods and also since the Tertiary epoch. Large areas are overlain with trachyte, basalt, obsidian, tuff and pumice. The most conspicuous features of the entire region, Mount Ararat (16,930 ft.) and Mount Alagöz (13,440 ft.), are both solid masses of trachyte; and both rise above the limits of perpetual snow. Extinct volcanoes are numerous in several of the ranges, e.g. Akmangan, Mokry, Karabakh and Egri-dagh (see below). It is in this region of the Armenian highlands that the largest lakes of Caucasia are situated, namely, the Gok-cha or Sevanga (540 sq. m. in area) at an altitude of 6340 ft., the Chaldir-gol (33 sq. m.) at 6520 ft., and several smaller ones, such as the gols of Khozapin, Khopchalu, Arpa, Toporavan and Tabiztskhur, all situated between 6500 and 7000 ft. above sea-level. The principal water-divide in this highland region is, however, the range of Egri-dagh (Ararat), which just south of 40° S. forms for 100 m. the boundary between Russian and Turkish Armenia, having Ararat at its eastern extremity and the extinct volcano of Kessa-dagh (11,260 ft.) at its western. Its importance lies in the fact that it divides the streams which flow into the Black Sea and Caspian from those which make their way into the Persian Gulf. The Egri-dagh possesses a sharply defined crest, ranges at a general elevation of 8000 ft., is bare of timber, scantily supplied with water, and rugged and deeply fissured.

The transverse water-parting between the Black Sea and the Caspian begins on the south side of the main range of the Caucasus, at Mount Zikara (12,560 ft.), a little south-west of Kasbek, and runs south-west along the sinuous crests of the Racha, Suram or Meskes (3000-5000 ft.), Vakhan (10,000-11,000 ft.), Arzyan (7000-10,000 ft.), and its continuation the Soganluk, thus linking the Caucasus ranges with those of the Armenian highlands. This line of heights separates the basins of the Chorokh and the Rion (Black Sea) from those of the Aras and the Kura (Caspian Sea). North of the Caucasus ranges the water-divide between these two seas descends from Mount Elbruz along the Sadyrlar Mountains (11,000 ft.), and finally sinks into the Stavropol “plateau” (1600 ft.). But the main axis of the transverse upheavals would appear to be continued in a north-eastern direction in the Andi and other parallel ranges of Daghestan, as stated under [Caucasus].

The population in this region consists principally of Armenians, Tatars, Turks, Kurds, Ossetes, Greeks, with Persians, Tates and a few Russians (see particulars below).

Climate.—Owing in part to the great differences in altitude in different regions of Caucasia and in part to the directions in which the mountain ranges run, and consequently the quarters towards which their slopes face, the climate varies very greatly according to locality. Generally speaking, it may be characterized as a climate of extremes on the Armenian highlands, in the Kura valley and in northern Caucasia, and as maritime and genial in Lenkoran, on the Black Sea coastlands, and in the valley of the Rion. The greatest recorded range of temperature is at Erivan (altitude 3230 ft.), namely, of 64° between a January average of 14.9° and an August average of 78.8° F. At Sukhum-kaleh, on the Black Sea, the corresponding range is only 27.3°, between a January average of 48.8° and an August average of 76.1°. The highest mean temperatures for the whole year are those of Lenkoran (60.3°) and of Sukhum-kaleh and Poti (about 58°), and the lowest at Ardahan (5840 ft.), in the province of Kars, namely, 37.9°, and at Gudaur (7245 ft.), a few miles south of Kasbek, namely, 38.6°. The following table gives particulars of temperature averages at a few typical places:—

Place.Altitude.Annual
Mean.		January
Mean.		July
Mean.
Stavropol203047.0°24.0°70.0°
Vladikavkaz234547.3°23.4°68.0°
Gudaur724538.6°20.3°57.2°
Bakuon Caspian58.0°38.0°80.0°
Tiflis149055.0°32.0°76.5°
Batumon Black Sea59.0°42.0°75.0°
Sochion Black Sea56.3°40.3°76.1°
Lenkoranon Caspian60.3°39.0°80.6°
Erivan317051.0°51.0°75.0°

In respect of precipitation the entire region of Caucasia may be divided into two strikingly contrasted regions, a wet and a dry. To the former belong the Black Sea littoral, where the rainfall averages 59 to 93 in. annually, and the valleys that open upon it or are exposed to winds blowing off it, in which the rainfall varies, however, from 20 in. (Abbas-tuman, Borzhom) to 60 (Kutais). In Lenkoran also the rainfall averages 40 to 50 in. in the year. Between 16 and 40 in. fall as a rule at the northern foot of the Caucasus (Mozdok, Pyatigorsk) and in the Kura valley (Tiflis, Novo-bayazet). On the Armenian highlands and on the steppes north of Pyatigorsk the rainfall is less than 12 in. annually, and even in some places less than 8 in., e.g. at the foot of Ararat. Most rain falls at Batum and at Lenkoran in the autumn, in northern Caucasia and in Transcaucasia in spring and summer, but in the vicinity of the Sea of Azov in winter.