Iturup (; Ainu: エﾂﾟヲロプシㇼ, Etuworop-sir; , Etorofu-tō) is one of the Kuril Islands. It is the largest and northernmost island in the southern Kurils, which are controlled by Russia but also claimed by Japan (see Kuril Islands dispute). Japan considers a site on Iturup to be its northernmost point.