World Facts

The Longest Rivers in Mongolia

The Orkhon River is the longest river in Mongolia.

Mongolia is a sovereign state in East Asia. There are more than 4,000 rivers in Mongolia. Many of the country's largest waterways are located in the Northern Arctic Basin, which is situated in northern and central Mongolia. Most of the rivers are seasonal, with massive discharge during the summer, when snow melts and rainfall increases. During the winter, most of the rivers freeze and some even act as roadways. Rivers in the east flow into the Pacific, while those in the south and west drain into lakes. The Orkhon River is the longest river in Mongolia.

The Longest Rivers in Mongolia

Orkhon River

The Orkhon River flows for 698 miles from its source in the Khangai Mountains to its mouth at the Selenga River, which flows north to Lake Baikal in Russia. The two major tributaries of the Orkhon River are the Tamir and Tuul rivers. Although the Selenga discharges more water, it is significantly shorter than the Orkhon River. The ruins of ancient capitals of the Mongol Empire and the Uyghur Kingdom are both located along the Orkhon River, and the Orkhon Valley has been designated as a UNESCO World Heritage Site.

Kherlen River

The Kherlen River, which is also referred to as the Kerulen, rises in the southern slopes of the Khentii Mountains, close to Burkhan Khaldun Mountain, within the Khan Khentii Strictly Protected Area. The river flows east through the Khentii Province before crossing the eastern Mongolian steppe, and then flows into China. The river has a total length of 677 miles from its source to its mouth in Hulun Lake, which is located in the Inner Mongolia region of China.

Tuul River

The Tuul River flows for 437 miles, from its source in the Khan Khentii Strictly Protected Area to its mouth at the Orkhon River. The river is considered sacred to the Mongol people, who refer to it as the Khatan (Queen) Tuul. Additionally, the palace of leader Wang Khan was located along the riverbank. The river flows through the southern edge of Mongolia's capital, Ulaanbaatar, before draining into the Orkhon River, which flows to the Selenga River. The Tuul River is among the few rivers in Mongolia that provides a habitat for the endangered sturgeon.

Water Pollution in Mongolia

The mining industry is the largest threat to clean water in Mongolia. After the collapse of the Soviet Union, the Mongolian government allowed miners to operate with few regulations, given that mining benefitted the economy. However, the mining industry dumped significant amounts of wastewater and other raw materials into the rivers, leading to extensive water pollution. Despite the eventual introduction of laws designed to protect Mongolia's rivers and water catchment areas, about 350 million cubic feet of untreated wastewater continue to be discharged into waterways each year.

List of the Longest Rivers in Mongolia

RankRiverLength (km)
1Orkhon1,124
2Kherlen1,090
3Tuul704
4Zavkhan670
5Selenge593
6Hovd516
7Eg475
8Ider452
9Delgermörön445

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