The also known as Tokaido corridor is the name for the megalopolis in Japan extending from Ibaraki Prefecture in the north all the way to Fukuoka Prefecture in the south, running for almost 1,200 km. The urbanization zone runs mainly along the Pacific coast (hence the name) of Japan from Kantō region to Osaka, and the Inland Sea (on both sides) to Fukuoka, and is concentrated along the Tōkaidō-Sanyō rail corridor. A view of Japan at night clearly shows a rather dense and continuous strip of light (that demarcates urban zones) that delineates the region.

Although it contains the majority of Japan's population, references to it in Japanese are mainly economic or regional in nature. The term was first used in 1960 in an Economic Commission Subcommittee Report formed to double the national income. At that time, it was identified as the core of the nation's industrial complex. The region is specifically defined by the Ministry of International Trade and Industry as the following prefectures: Ibaraki, Saitama, Chiba, Tokyo, Kanagawa, Shizuoka, Aichi, Gifu, Mie, Osaka, Hyogo, Wakayama, Okayama, Hiroshima, Yamaguchi, Fukuoka, and Oita. As economic development (along with urban development) spilled over to nearby regions, they were added to this list.

The Sea of Japan has a much less well-developed string of cities, called, very pejoratively (literally: the rear of Japan), stretching 1000 km from Akita to Yamaguchi. It is often referenced in relation to the Taiheiyo belt.

Major cities

Listed from north to south:

• Greater Utsunomiya (pop. 900,000) including Nikkō, Kanuma, Tochigi, Oyama, Shimotsuke.

• Greater Maebashi (pop. 1,500,000) including Takasaki, Kiryu, Isesaki, Ota, Ashikaga, Sano, and Tatebayashi.

• Greater Ibaraki (pop. 1,300,000) including Mito, Tsuchiura, Hitachinaka, Hitachi, Tsukuba.

• Greater Tokyo (pop. 35.5 million)

• Mt. Fuji Area (pop. 700,000) including Gotemba, Atami, Numazu, Fujinomiya, Fujieda, Mishima

• Greater Shizuoka (pop. 1,000,000)

• Greater Hamamatsu (pop. 1,100,000) including Kakegawa and Iwata.

• Toyohashi (pop. 400,000)

• Greater Nagoya (Chūkyō Metropolitan Area) (pop. 8,000,000)

• Greater Osaka (pop. 17,000,000) including Osaka, Kyoto, Kobe, Sakai, and Higashiosaka

• Greater Nara (pop. 1,000,000)

• Himeji (pop. 500,000)

• Tokushima (pop. 300,000)

• Greater Okayama (pop. 1,900,000) including Okayama, Kurashiki, Takamatsu, Marugame, Sakaide, Tamano, Soja.

• Fukuyama-Kure (pop. 1,100,000) including Onomichi, Mihara, Higashi Hiroshima.

• Greater Hiroshima (pop. 1,300,000) including Hatsukaichi.

• Greater Matsuyama (pop. 1,050,000) including Imabari, Saijō, Niihama, Shikokuchūō.

• Iwakuni - Yamaguchi (pop. 1,000,000) including Ube, Hofu, Shunan, Hikari, Sanyō-Onoda.

• Kanmon Straits (pop. 1,700,000) including Shimonoseki and Kitakyushu including Iizuka.

• Greater Fukuoka (pop. 2,500,000) including Saga and Kasuga.

• Kurume (pop. 300,000)

• Nakatsu (pop. 215,000)

• Oita (pop. 700,000) including Beppu.

Total population: approx 82.9 million

See also

• List of metropolitan areas in Japan by population
• Northeast Megalopolis

References

1. Satellite images of stable night time lights in Japan