The Irtysh River (Mongolian:Эрчис мөрөн/Erchis, "erchleh", "twirl"; Russian:Иртыш; Kazakh:Ертiс / Yertis; Chinese: 额尔齐斯河, pinyin: É'ěrqísī hé; ******: ئېرتىش, Иртүш; Tatar: CyrillicИртеш, Latinİrteş) is a river in Russia, China, and Kazakhstan. It is the chief tributary of the Ob River.