Irtysh
The Irtysh (Old Turkic: 𐰼𐱅𐰾:𐰇𐰏𐰕𐰏, romanized: Ertis ügüzüg,[1] Mongolian: Эрчис мөрөн, Erchis mörön,[2] "erchleh", "twirl"; Russian: Иртыш; Kazakh: Ертіс, Ertis, هرتىس; Chinese: 额尔齐斯河, pinyin: É'ěrqísī hé, Xiao'erjing: عَعَرٿِسِ حْ; Uyghur: إيرتيش, Әртиш, Ertish; Tatar: Иртеш, İrteş, ﻴﺋرتئش, Siberian Tatar: Эйәртеш, Eya’rtes’) is a river in Russia, China, and Kazakhstan. It is the chief tributary of the Ob and is also the longest tributary river in the world.
| Irtysh | |
|---|---|
 Irtysh watershed | |
| Location | |
| Country | Mongolia, China, Kazakhstan, Russia |
| Cities | Oskemen, Semey, Pavlodar, Omsk, Tobolsk, Khanty-Mansiysk |
| Physical characteristics | |
| Source | |
| • location | near Mang-tai-ch’ia-ta-fan pass, Altai Mountains, Xinjiang, China |
| • coordinates | 47°52′39″N 89°58′12″E |
| • elevation | 2,960 m (9,710 ft) |
| Mouth | Ob |
• coordinates | 61°05′24″N 68°49′15.60″E |
| Length | 4,248 km (2,640 mi) |
| Basin size | 1,643,000 km2 (634,000 sq mi) |
| Discharge | |
| • average | 2,150 m3/s (76,000 cu ft/s) (near Tobolsk) |
| Basin features | |
| Progression | Ob→ Kara Sea |
The river's source lies in the Mongolian Altai in Dzungaria (the northern part of Xinjiang, China) close to the border with Mongolia.
The Irtysh's main tributaries include the Tobol, Demyanka and the Ishim. The Ob-Irtysh system forms a major drainage basin in Asia, encompassing most of Western Siberia and the Altai Mountains.