Oleny Island is a single island in the Kara Sea just a few kilometers offshore, north of the coast of one of the arms of the Gyda Peninsula in North Siberia. It is covered with tundra and swamps and it is 53 km in length and its average width is 27 km, having an area of 1197 km². Its latitude is 72° 24' N and the longitude 77° 45' E. To the northeast lies Sibiryakov Island.