Irkutsk (Russian: Ирку́тск) is one of the largest cities in Siberia and the administrative center of Irkutsk Oblast, situated 5,185 kilometers (3,222 mi) by rail from Moscow. Population: 593,604 (2002 Census); 626,135 (1989 Census); 500,000 (1975); 49,106 (1900); 35,512 (1875).