THE CAUCASUS MOUNTAINS are the highest mountain range in Europe, but lie at the very eastern extremity of what geographers consider to be Europe. In fact, the dividing line traditionally used to divide Europe from Asia runs directly through the center of the range.
Forming both a barrier and a connector for civilizations between the BLACK and CASPIAN seas, and between the MIDDLE EAST and the STEPPEs to the north, the cultures of the Caucasus region have occupied a central place for trade and cultural exchange for over 2,000 years. The range's isolated valleys have served as a haven for refugees and immigrants from many areas, resulting today in one of the most ethnically and linguistically diverse regions on Earth.
The two major ranges of the Caucasus, the Great Caucasus and the Lesser Caucasus, stretch east to west for nearly 550 mi (900 km) from the eastern shore of the Black Sea to Baku on the Caspian. Elevations generally rise from both ends towards the central range, in which the highest peaks are located, including Mount ELBRUS, the highest peak (18,506 ft or 5,642 m). The various ranges and subranges are similar in their mountain characteristics: jagged and generally impassable. Climatically, however, west and east differ dramatically, due to the effects of moisture off the Black Sea and the contrasting dryness of the Caspian. As a result, the western ranges tend to have a subtropical climate, with heavy vegetation, while the eastern part of the range is semidesert and barren. The Caucasus Mountains share many characteristics with the ALPS, but their peaks are generally much taller, averaging 6,000 to 9,000 ft (2,000 to 3,000 m)—over 20 summits are higher than Mont Blanc. Its ridges are mostly parallel, running from west-northwest to east-southeast, but are broken up by horseshoe-shaped ridges with glacier-filled basins. Many of these are unstable, subject to frequent landslides and avalanches. Most of the ridges are more continuous than those of the Alps, resulting in a greater barrier, with only one major pass—through the dramatic Daryal gorge—and several smaller ones that are usually obstructed by snow. As a result of several of these features, the Caucasus Mountains are generally more inhospitable than the Alps and have a more wild and austere quality.
The Caucasus ranges were formed in the same manner (and at roughly the same time) as the Alps, through tectonic plate collision between the Arabian Plate and the Eurasian Plate. This movement continues today, manifesting itself through regular earthquakes. Many years ago there was volcanic activity in the region, creating some of the tallest cones (like Elbrus), but these volcanoes are currently extinct, with the exception of the active mud volcanoes of the Apsheron Peninsula, which juts 53 mi (85 km) into the Caspian Sea. It is here where the most important of the region's natural resources are located—the offshore oilfields of AZERBAIJAN. Other oil resources are found on the northern slopes, near the cities of Grozny and Krasnodar. At the western extremity of the range, the Caucasus also extend a bit further than the land they occupies, forming the low mountains of the Taman Peninsula, which nearly joins with the Kerch Peninsula of the Crimea, across the mouth of the Sea of Azov.
The Great Caucasus range is divided from the Lesser Caucasus by a parallel valley, the Transcaucasian depression, averaging 60 mi (100 km) in width. This depression connects the Black Sea coast with the Caspian Sea, where elevations dip below sea level. The depression is divided in two by a low range perpendicular to the main ranges, the Surami, which forms the climatic barrier between the moist west and the dry east. To the west of this range lies the Colchis Lowlands, the “Riviera of the Caucasus,” with grapes and olives and holiday resorts. To the east lies the Kura Lowland, dominated by the Kura River, the longest river in the Caucasus, which flows out of the Armenian Highlands, past the industrial city of Tbilisi to the Caspian Sea near Baku. Near its mouth, the Kura is joined by the Araks River, which starts in eastern TURKEY and forms the border of ARMENIA and Azerbaijan with Turkey and IRAN to the south. This basin was actually part of the Caspian Sea in times of higher water levels. Other major rivers of the Caucasus region flow north, cutting gorges through the Great Caucasus: the Kuban, which flows into the Black Sea, and the Terek and Sulak, which flow across Dagestan into the Caspian.
The Great Caucasus is itself divided into several ranges, the most important being the Main Range and the Front Range. The Main Range forms the drainage divide between north and south. A few kilometers to the north, the Front Range is less continuous, but has the highest peaks in the entire system (the extinct volcanic cones like Elbrus). To the north lies the Stavropol Plateau, which gradually slopes to the steppes of southern RUSSIA. Other prominent peaks besides Elbrus in the central section of the Great Caucasus include Dykh-Tau and Shkara, both just over 16,500 ft (5,000 m), and the slightly lower Koshtan and Kazbek. Mount Kazbek (also called Mkinvari) marks the easternmost part of the central range and is the second-most popular peak for mountaineers, after Elbrus. The eastern end of the range descends gradually toward the Caspian Sea, breaking up into isolated massifs rather than continuous chains. This region of low dry hills resembles the badlands of SOUTH DAKOTA. The Lesser Caucasus are less defined as parallel west-to-east ranges; instead they generally merge into the Armenian Highlands, and the Anatolian and Iranian plateaux to the south. Here the peaks are generally lower, 3,000 to 7,000 ft (1,000 to 2,000 m), and several of the elevated valleys have been filled in by volcanic material forming an elevated surface.
Three nations with completely different ethnic and linguistic roots dominate the southern slopes of the Caucasus (called Transcaucasia by Russocentrics, but more acceptably, the South Caucasus): GEORGIA, Armenia and Azerbaijan. Each of these has numerous ethnic minorities within its borders, many of which are currently embroiled in struggle for autonomy or outright independence, for example, Ajaris, Ossetians, and Abkhazians. North of the main range, Russians form the majority of the population (having settled there during the reign of Catherine the Great in the late 18th century) but also contend with separatist movements of Caucasian peoples, notably the Chechens, Kabardians, and the many tribes of Dagestan. The crest of the Great Caucasus generally forms the border between Russia and the South Caucasian states, but their other borders are not as easily defined by the confusing knot of the Lesser Caucasus, resulting in several contemporary border conflicts, notably Nagorno-Karabagh, claimed by Azerbaijan and occupied by Armenia. Among the resources quarreled over are oil, which CHECHNYA has and Russia wants, and water, which Armenia has and Azerbaijan wants. Azerbaijan has access to the vast offshore reserves of Caspian Sea oil but needs the cooperation of Georgia to deliver its product to the West via pipelines to the Black Sea. Having achieved independence at the dissolution of the Soviet Union in 1991, much of the region still depends on Russia for electricity and other basic needs, despite its desire to reconnect ties both towards western Europe and the Middle East.