Geography. Orkhon aimag is located in Central Mongolia, bordering with Selenge aimag to the east, Bulgan to the west. Orkhon province is situated in the forest-steppe sub region of Khangai Mountain region, occupying the midlands of Buren Mountain range and Orkhon and Selenge River Basin. It is surrounded by Erdenet-Ovoo, Bayan-Undur, Deeliin Nuruu Mountains which are elevated at 1,600 to 1,700m above sea level. Majority of the mountains in Orkhon aimag are medium-high mountains. Orkhon is considered to be the smallest aimag of Mongolia.
Meteorology. Orkhon aimag has a continental climate. Winter season is very cold, starts in early November and ends around in the end of March. The lowest ever recorded temperature is -40°C and hottest is +39°C. On average, temperatures drop down to -20°C and increases up to +30°C. Mostly calm, stable weather dominates the aimag. Annual average air temperature is +0.8°C and average precipitation is 371.8m in a year with high rain and snow falls. April and May are the windiest months, January is the coldest and July is the hottest month of the year. Wind speed reaches to 28m/sec occasionally. During the rainy times precipitation rate can increase by 80% or reaches 250 to 300mm. Orkhon Aimag, situated in Sothern Valley of Buren Mountain of Khangai Range, surrounded by 200-500m high Erdenet Ovoo, Bayan Undur, Delen mountains, has a unique microclimate.
Soil. The soil consists of the steppe, desert-steppe, and mountain umber powder like soil with carbonate. One of the 10 biggest copper deposits of the world is located in Orkhon aimag. Erdenetiin Ovoo Mountain of Erdenet city that lies in Orkhon and Selenge River Basin, is rich with copper and molybdenum. Erdenet Copper and Molybdenum Concentration Plant started its operations in 1978. The copper ore ledgement stretches for 25km to the north with the width of 1.5 to 3km. Erdenetiin Ovoo Mountain used to be 1,607m in height before the exploitation.