an urban-type settlement in Sysert’ Raion, Sverdlovsk Oblast, RSFSR; located on the Iset’ River (Ob’ basin), 4 km from the Kol’tsovo railroad station (20 km southeast of Sverdlovsk). Population, 7,100 (1968). Bol’shoi Istok produces sanitary-engineering equipment. It has a flour mill and a plant manufacturing soft packaging materials. Peat is extracted near Bol’shoi Istok.