Geography of the Orxon Valley
The Orxon river valley presents natural and geographical conditions which, relative to those of the surrounding region, are highly suitable for human livelihood. Consequently the Orxon Valley has been occupied by a succession of nomadic peoples at various stages in history, as exemplified by an abundance of historic monuments and archaeological findings: dwellings and sites of artisanal production dating from the Paleolithic, Mesolithic and Neolithic; slab graves, keregsur, deer stones and petroglyphs from the Bronze Age and early Iron Age; ruins of cities and temples, graves, steles, and statues of humans and animals from the Hunnu, Türkic, Uighur, Kidan and Mongol state periods; and temples and monasteries, ruins of permanent dwellings, and monuments related to the spread of Buddhism in Mongolia. Such monuments attest to the fact that the main populations of this region, the Central Asican nomads, not only herded animals but also developed a certain degree of sedentary activity, constructing permanent settlements and performing artisanal and agricultural activites. Yet we can see that the nomadic populations were truly able to satisfy their needs and aspirations in harmony with the surrounding natural environment. The Orxon River is one of the longest rivers in Mongolia, flowing 1124 kilometres from its source at the eastern foot of the Suvarga Xairxan mountain of the Xangai range, through the steppes of Central Mongolia, eventually joining up with the Selenge River along the northern border of the country. The historic sites and monuments of the Orxon Valley Cultural Landscape are located in the flood plain near the source of the river and in its surrounding mountains, ranging in absolute elevation from approximately 1350 m to 2268 m. From the town of Xarxorin, the Orxon River enters a marshy area and branches off into several streams. In the vicinity of the Orxon Valley monuments, its width ranges from 18 to 28 metres.
Climatically the Orxon Valley area belongs to the continental zone, characterized by cool summers and severe winters. There is an average of 80-100 clear days per year. The average annual temperature is 0.80C, while the average daily temperature ranges from -180C in January to +150C in July. The average annual precipitation level is 332 mm – but this amount varies considerably, and periodic years of drought and flood are not uncommon. There is generally the least precipitation in winter (2.4-3.0 mm), and the most in summer; in the three months of summer an average of 240.5 mm of precipitation falls (79% of the annual average), and 95% of all precipitation falls between April and October. The first snowfall occurs on average around the 14th of September, while the latest snowfall occurs around the 27th of May. Lasting snow generally occurs in the middle of November and melts around the 10th of March, lasting for an average total of 121 days. The average depth of snow is 9 cm, while the deepest is 25-30 cm or more. Wind patterns follow the valley and mountains; at Xarxorin the wind comes from the southwest 19-41% of the time and from the northwest 13-28% of the time. Overall the average windspeed is 3.6 m/s, with relatively stronger winds in summer, despite the relatively lower frequency of winds. Forested steppe covers the mountainous part of the region, while semi-arid steppe covers the plains within the valley. The peaks and northern slopes of Tövxen Xan, Öndör Ovoot, Öndör Sant, Bayanzurx, Nart, and Chavgants mountains are heavily wooded. The primary forest vegetation is Siberian larch and, at higher elevations, cedar. The forest following the main mountain ridge is primarily constituted of larch. Below the limits of the forest the terrain is constituted of a meadow area broken by multiple small ravines. Overall the Orxon Valley Cultural Landscape, situated in the Xangai range and Orxon-Selenge basin geomorphological zones, covers a wide range of geographical conditions. Tövxen Monastery is located on the western bank of the Orxon river, at the peak of Öndör-Ovoot Mountain (2312 m above sea level), at the extremity of the eastern branch of the Xangai mountains. The remaining monuments are situated in the plain of the Orxon Valley (Erdene Zuu: 1460 m, Xar Balgas: 1380 m, Xöshöö Taidam: 1375 m above sea level). Öndör Ovoot Mountain, the site of Tövxen Monastery, is the watershed point for the local streams which flow into the Orxon river, but the neighbouring Öndör Sant mountain (2364.6 m) and Bayanzürx mountain (2254.2 m), located to the north-east, and Sharil Öndör (1943.2 m) and Ix Moilt (2064.2 m) mountains, located to the south of the Orxon river, create a large system constituting the end of the eastern branch of the Xangai mountain range. This mountainous formation is principally constituted of sedimentary rocks such as shale, argelite, and alevrolite formed during the devonian and carboniferous periods of the paleozoic era (300-400 million years ago), and igneous rocks which have broken through the latter. Thus the peaks of Öndör Ovoot, Öndör Sant, Bayanzürx and Ix Moilt mountains are generally constituted of granite crags and cliffs, projecting ridges, and protruding rocks. One example of such a formation is Öndör Ovoot mountain, site of Tövxen Monastery, where 14 temples were constructed in the gaps between granite cliffs measuring 20 metres or more in height. The abundance of rocks in the area contributed to the widespread construction of granite statuary and funerary architecture by early inhabitants of the region, in addition to its noticeable influence on local monastic architecture. The Orxon river originates in the vicinity of Xar Xorin, becoming a proper river in the steppe after the edge of the Xangai mountains, and developing many branches, along which there is a proliferation of small marshes. The rocks of this valley are primarily variegated and grey gravel and pebble deposits from the mid to upper quaternary period, although Elsen Tal ("Sandy Plain"), the area in which the ruins of Xar Balgas are located, is characterized by sediment deposits from the lower to mid Jurassic period. Geologists have identified 50 metre-high terraces in the section of the Orxon river valley above Xar Xorin, which are constituted of fine gravel river deposits, demonstrating that in early times the Orxon was a much wider river than it is today. The density of the Orxon river is 0.10-0.20 km/km2. The main water source of the Orxon is rainfall but groundwater and spring meltoff are also important contributors. The average temperature of the water is 2.6ºC in April, 11.3ºC in May, and 18ºC in July. The water of the Orxon river is quite pure and therefore potable by humans and animals.
The river is inhabited by a variety of fish species, including lenok, pike, taimen, perch, grayling, sazan, roach, goldfish, and sheat-fish. The mountain meadows or "mountainous steppe" features are encountered below the treeline and on the south side of medium-sized mountains. In this region, characterized by a relatively infertile soil, are located plants such as koeleria marantha, stipa krylovii, festula lenensis, artemisia frigida, agropyron ristata and lemus chenensis. The dry steppe landscape to the north, located along lower hills and mountains, is home to a variety of grasses and similar plant species including festuca, poa, stipa, artemisia frigida, agropyron cristata, arenaria capilaris, heperpappus artasaca, veronica incana and potentilla. The meadow landscape extending through the valleys of the Orxon, Xögshin, Xarz, Saran and other local rivers and streams contains a variety of soil types, and is home to vegetation species such as agrostis, elymus chenensis, poa, geranum, songasorva officianalis, carex, potentilla, and artemisia adamsii.
 | In commemoration of the legacy and teachings of His Holiness Dulduit Danzanravzhaa Fifth Wrathful Noble Xutagt of the Great Gobi (1803-1856) I did not overbearingly sophize Nor preach with pride and arrogance But having found a sense in this world Spoke the truth of my dear heart. |   |