a river in Perm’ Oblast, RSFSR; a left tributary of the Sylva River (basin of the Kama Reservoir). Length, 214 km; basin area, 6,110 sq km. There are karst phenomena in the Iren’ basin. The river, fed mainly by snow, has a mean annual flow rate of 35.5 cu m per sec near its mouth. It freezes in November; the ice breaks up in April. It can be used for floating logs. The city of Kungur is situated at the mouth of the Iren’.