Stretching from Hokkaido, Japan to Kamchatka, Russia, separating the Sea of Okhotsk from the north Pacific Ocean, are a string of volcanic islands called Kuril Islands. The archipelago belongs to Russia, but Japan claims the four southernmost islands, including the two largest ones—Iturup and Kunashir.Iturup island is very beautiful with volcanic massifs and mountain ridges. About a dozen calc-alkaline volcanoes running along the length of the elongated island form the backbone of the island. The shores of the island are high and abrupt and is marked by white pumice cliffs and black hexagonal pillars. The island also contains some high waterfalls.