Irkut (Russian: Ирку́т, Mongolian: Эрхүү голBuryat: Эрхүү гол) is a river in the Buryat Republic and Irkutsk Oblast of Russia. It is the Angara River's left tributary. It flows out of lake Ilchir which is situated 50 km away from the highest pick of the Easten Sayan mountains Munku-Sardyk. The length of the river is 488 kilometers (303 mi). The area of its basin is 15,000 square kilometers (5,800 sq mi). The Irkut River freezes up in late October or mid-November and stays icebound until late April or early May. The city of Irkutsk is located at the mouth of the Irkut River on the Angara River.