The Kuril Islands are a volcanic archipelago stretching about 1,300 km between Japan's Hokkaido and Russia's Kamchatka Peninsula, comprising 56 islands that separate the Sea of Okhotsk from the Pacific Ocean. Sitting on the Pacific "Ring of Fire," the chain features around 100 volcanoes (40 active) and frequent seismic activity, including a magnitude 8.5 earthquake in 1963 and a major eruption at Raikoke in 2019 that sent ash 13 km high. The climate is harsh—subarctic with foggy summers and stormy winters—supporting vegetation from tundra in the north to dense spruce forests in the south, with the highest peak, Alaid Volcano, reaching 2,339 meters. The islands have been under Russian control since the Soviet invasion in 1945, but Japan claims the four southernmost islands (Iturup, Kunashir, Shikotan, and the Habomai islets), creating the ongoing Kuril Islands dispute known in Japan as the "Northern Territories." The name "Kuril" likely originates from the Ainu word kur meaning "man," though Russian explorers later linked it to kurit ("to smoke") because of the islands' constant volcanic plumes.