Hokkaido in the context of "Sea of Okhotsk"

Japan is divided into 47 prefectures (都道府県, todōfuken, [todoːɸɯ̥ꜜkeɴ] ), which rank immediately below the national government and form the country's first level of jurisdiction and administrative division. They include 43 prefectures proper (県, ken), two urban prefectures (府, fu: Osaka and Kyoto), one regional prefecture (道, dō: Hokkaidō) and one metropolis (都, to: Tokyo). In 1868, the Meiji Fuhanken sanchisei administration created the first prefectures (urban fu and rural ken) to replace the urban and rural administrators (bugyō, daikan, etc.) in the parts of the country previously controlled directly by the shogunate and a few territories of rebels/shogunate loyalists who had not submitted to the new government such as Aizu/Wakamatsu. In 1871, all remaining feudal domains (han) were also transformed into prefectures, so that prefectures subdivided the whole country. In several waves of territorial consolidation, today's 47 prefectures were formed by the turn of the century. In many instances, these are contiguous with the ancient ritsuryō provinces of Japan.

Each prefecture's chief executive is a directly elected governor (知事, chiji). Ordinances and budgets are enacted by a unicameral assembly (議会, gikai) whose members are elected for four-year terms.

Japan is often divided into regions, each containing one or more of the country's 47 prefectures at large. Sometimes, they are referred to as "blocs" (ブロック, burokku), or "regional blocs" (地域ブロック, chiiki burokku) as opposed to more granular regional divisions. They are not official administrative units, though they have been used by government officials for statistical and other purposes since 1905. They are widely used in, for example, maps, geography textbooks, and weather reports, and many businesses and institutions use their home regions in their names as well, for example Kyushu National Museum, Kinki Nippon Railway, Chūgoku Bank, and Tōhoku University.

One common division groups the prefectures into eight regions. In this arrangement, of the four main islands of Japan, Hokkaidō, Honshu, Shikoku, and Kyūshū, each form their own region, with Kyūshū also including the Satsunan Islands. The largest island, Honshū, is split into five regions. Okinawa Prefecture is usually considered part of Kyūshū, but it is sometimes treated as its own ninth region.

Japan is an archipelagic country comprising a stratovolcanic archipelago over 3,000 km (1,900 mi) along the Pacific coast of East Asia. It consists of 14,125 islands. The five main islands are Hokkaido, Honshu, Kyushu, Shikoku, and Okinawa. The other 14,120 islands are classified as "remote islands" by the Japanese government. The Ryukyu Islands and Nanpō Islands are south and east of the main islands.

The territory covers 377,973.89 km (145,936.53 sq mi). It is the fourth-largest island country in the world and the largest island country in East Asia. The country has the 6th longest coastline at 29,751 km (18,486 mi) and the 8th largest Exclusive Economic Zone of 4,470,000 km (1,730,000 sq mi) in the world.

Sakhalin (Russian: Сахалин, IPA: [səxɐˈlʲin]) is an island in Northeast Asia. Its north coast lies 6.5 km (4.0 mi) off the southeastern coast of Khabarovsk Krai in Russia, while its southern tip lies 40 kilometres (25 mi) north of the Japanese island of Hokkaido. An island of the West Pacific, Sakhalin divides the Sea of Okhotsk to its east from the Sea of Japan to its southwest. It is administered as part of Sakhalin Oblast and is the largest island of Russia, with an area of 72,492 square kilometres (27,989 sq mi). The island has a population of roughly 500,000, the majority of whom are Russians. The indigenous peoples of the island are the Ainu, Oroks, and Nivkhs, who are now present in very small numbers.

The island's name is derived from the Manchu word Sahaliyan (ᠰᠠᡥᠠᠯᡳᠶᠠᠨ), which was the name of the Qing dynasty city of Aigun. The Ainu people of Sakhalin paid tribute to the Yuan, Ming, and Qing dynasties and accepted official appointments from them. Sometimes the relationship was forced but control from dynasties in China was loose for the most part.

The Kuril Islands or Kurile Islands are a volcanic archipelago administered as part of Sakhalin Oblast in the Russian Far East. The islands stretch approximately 1,300 km (810 mi) northeast from Hokkaido in Japan to Kamchatka Peninsula in Russia, separating the Sea of Okhotsk from the north Pacific Ocean. There are 56 islands and many minor islets. The Kuril Islands consist of the Greater Kuril Chain and, at the southwest end, the parallel Lesser Kuril Chain. The group termed the 'South Kurils' consists of those of the Lesser Kuril Chain together with Kunashir and Iturup in the Greater Kuril Chain. The Vries Strait between Iturup and Urup forms the Miyabe Line dividing the North and South Kurils. The Kuril Islands cover an area of around 10,503.2 square kilometres (4,055.3 sq mi), with a population of roughly 20,000.

The islands have been under Russian administration since their 1945 invasion by the Soviet Union near the end of World War II. Japan claims the four southernmost islands, including two of the three largest (Iturup and Kunashir), as part of its territory, as well as Shikotan and the unpopulated Habomai islets, which has led to the ongoing Kuril Islands dispute. The disputed islands are known in Japan as the country's "Northern Territories".

Taiga or tayga (/ˈtaɪɡə/ TY-gə; Russian: тайга́, IPA: [tɐjˈɡa]), also known as boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches. The taiga, or boreal forest, is the world's largest land biome. In North America, it covers most of inland Canada, Alaska, and parts of the northern contiguous United States. In Eurasia, it covers most of Sweden, Finland, much of Russia from Karelia in the west to the Pacific Ocean (including much of Siberia), much of Norway and Estonia, some of the Scottish Highlands, some lowland/coastal areas of Iceland, and areas of northern Kazakhstan, northern Mongolia, and northern Japan (on the island of Hokkaido).

The principal tree species, depending on the length of the growing season and summer temperatures, vary across the world. The taiga of North America is mostly spruce; Scandinavian and Finnish taiga consists of a mix of spruce, pines and birch; Russian taiga has spruces, pines and larches depending on the region; and the Eastern Siberian taiga is a vast larch forest.

Fukushima Prefecture (福島県, Fukushima-ken; Japanese pronunciation: [ɸɯ̥.kɯꜜ.ɕi.ma, -kɯ.ɕi.maꜜ.keɴ]) is a prefecture of Japan located in the Tōhoku region of Honshu. Fukushima Prefecture has a population of 1,771,100 (as of 1 July 2023) and has a geographic area of 13,783.90 square kilometres (5,321.99 sq mi). Fukushima Prefecture borders Miyagi Prefecture and Yamagata Prefecture to the north, Niigata Prefecture to the west, Gunma Prefecture to the southwest, and Tochigi Prefecture and Ibaraki Prefecture to the south.

Fukushima is the capital and Iwaki is the largest city of Fukushima Prefecture, with other major cities including Kōriyama, Aizuwakamatsu, and Sukagawa. Fukushima Prefecture is located on Japan's eastern Pacific coast at the southernmost part of the Tōhoku region, and is home to Lake Inawashiro, the fourth-largest lake in Japan. Fukushima Prefecture is the third-largest prefecture of Japan (after Hokkaido and Iwate Prefecture) and divided by mountain ranges into the three regions of Aizu, Nakadōri, and Hamadōri.

The Tone River (利根川, Tone-gawa; Japanese pronunciation: [to.ne.ɡa.wa, -ŋa.wa], locally [to.neꜜ.ɡa.wa, -ŋa.wa]) is a river in the Kantō region of Japan. It is 322 kilometers (200 mi) in length (the second longest in Japan after the Shinano River) and has a drainage area of 16,840 square kilometers (6,500 sq mi) (the largest in Japan). It is nicknamed Bandō Tarō (坂東太郎); Bandō is an obsolete alias of the Kantō Region, and Tarō is a popular given name for an oldest son. It is regarded as one of the "Three Greatest Rivers" of Japan, the others being the Shinano River in northeastern Honshu and the Ishikari River in Hokkaido.