The Soviet Union is the largest country in the world and shares land borders with Scandinavia, Finland, Estonia (with the Latvian Soviet Socialist Republic), Lithuania and Poland (both with the Rykovgrad German Autonomous Oblast), Czechoslovakia, Hungary, Romania, Turkey, Iran, Afghanistan, Uyghurstan, Mongolia, Manchuria, and Korea. It also has maritime borders with Japanese island of Karafuto across the Strait of Tartary and with the U.S. state of Alaska across the Bering Strait. Extending across the entirety of Northern Asia and much of Eastern Europe, the Soviet Union spans nine time zones and incorporates a wide range of environments and landforms.