Iturup is one of the Kuril Islands. It was formerly known as Staten Island. It is the largest and northernmost island in the southern Kurils, ownership of which is disputed by Japan and Russia.
The island was Japanese territory since 1855 until the end of the Second World War in 1945, when Soviet forces took possession of all the Kurils and forced out Japanese residents. The island is still claimed by Japan, which considers a site on Iturup to be its northernmost point.
Iturup is located near the southern end of the Kuril chain, between Kunashiri and Urup. The town of Kurilsk, administrative center of Kurilsky District, is located roughly midway along its western shore.
Wikipedia https://en.wikipedia.org/wiki/Iturup
Coordinates 45°4'34.785" N 147°52'42.708" E