Iturup (Russian: Итуру́п and Oстров Итуру́п, Ostrov Iturup; Ainu: エツ゚ヲロプシㇼ, Etuworop-sir; Japanese: 択捉島, 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.
The island was Japanese territory until the end of the Second World War in 1945, when Soviet forces took possession of all the Kurils and forced out Japanese residents.
Iturup is located near the southern end of the Kuril chain, between Kunashiri (19 km to the SW) and Urup (37 km to the NE). The town of Kurilsk, administrative center of Kurilsky District, is located roughly midway along its western shore.
The strait between Iturup and Urup is known as the Vries Strait, after Dutch explorer Maarten Gerritsz Vries, the first recorded European to explore the area.
Iturup consists of volcanic massifs and mountain ridges. A series of a dozen volcanoes running NE to SW form the backbone of the island, the highest being Stokap (1,634 m) in the central part of Iturup. The shores of the island are high and abrupt. The vegetation mostly consists of spruce, larch, pine, fir, and mixed deciduous forests with alder, lianas and Kuril bamboo underbrush. The mountains are covered with birch and Siberian Dwarf Pine scrub, herbaceous flowers (including Fragaria iturupensis, the Iturup strawberry) or bare rocks.