Trans-Siberian Highway in the context of "Highway 1 (Australia)"

Irkutsk (/ɪərˈkutsk/ eer-KOOTSK; Russian: Иркутск, IPA: [ɪrˈkutsk]; Buryat and Mongolian: Эрхүү, Erhüü, [ɛrˈxuː]) is the largest city and administrative center of Irkutsk Oblast, Russia. With a population of 587,891 as of the 2010 Census, Irkutsk is the 25th-largest city in Russia by population, the fifth-largest in the Siberian Federal District, and one of the largest cities in Siberia.

Located in the south of the eponymous oblast, the city proper lies on the Angara River, a tributary of the Yenisei, about 850 kilometres (530 mi) to the south-east of Krasnoyarsk and about 520 kilometres (320 mi) north of Ulaanbaatar. The Trans-Siberian Highway (Federal M53 and M55 Highways) and Trans-Siberian Railway connect Irkutsk to other regions in Russia and Mongolia.

European route E30 is an A-Class European route from the port of Cork in Ireland in the west to the Russian city of Omsk, near the border with Kazakhstan in the east. For much of the Russian stretch, it follows the Trans-Siberian Highway and, east of the Ural Mountains, with AH6 of the Asian Highway Network, which continues to Busan, South Korea. The total length is 6,530 km (4,060 mi)—3,300 km (2,100 mi) from Cork to Moscow, and 3,230 km (2,010 mi) from Moscow to Omsk. The naming is by the United Nations Economic Commission for Europe (UNECE).