Taiheiyō Belt

[1] 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 (demarcating urban zones) that delineates the region.

[3] Although the Taiheiyō Belt contains the majority of Japan's population, references to the term 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.

[5] 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, Hyōgo, Wakayama, Okayama, Hiroshima, Yamaguchi, Fukuoka and Oita.

A map of the Taiheiyō Belt showing the Tōkaidō and Sanyō shinkansen routes.
A nighttime satellite photo comparison (to scale) of the Northeast Megalopolis in the United States (top) and the Taiheiyō Belt (bottom).
Major cities of Taiheiyō Belt