Taiheiyō Belt in the context of "Kansai Region"

Honshu (Japanese: 本州, Hepburn: Honshū; pronounced [hoꜜɰ̃.ɕɯː] ; lit. 'main province'), historically known as Akitsushima (秋津島; lit. 'dragonfly island'), is the largest of Japan's four main islands. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the seventh-largest island in the world, and the second-most populous after the Indonesian island of Java.

Honshu had a population of 104 million as of 2017, constituting 81.3% of the entire population of Japan, and mostly concentrated in the coastal areas and plains. Approximately 30% of the total population resides in the Greater Tokyo Area on the Kantō Plain. As the historical center of Japanese cultural and political power, the island includes several past Japanese capitals, including Kyoto, Nara, and Kamakura. Much of the island's southern shore forms part of the Taiheiyō Belt, a megalopolis that spans several of the Japanese islands. Honshu also contains Japan's highest mountain, Mount Fuji, and its largest lake, Lake Biwa.

This is a list of metropolitan areas (都市圏, toshiken) in Japan by population as defined by the Statistics Bureau of Japan (SBJ) and the Center for Spatial Information Service of the University of Tokyo. The region containing most of the people in Japan between Tokyo and Fukuoka is often called the Taiheiyō Belt.

The Tōkaidō Shinkansen (Japanese: 東海道新幹線; lit. 'East coast route, new main line') is a Japanese high-speed rail line that is part of the nationwide Shinkansen network. Along with the San'yō Shinkansen, it forms a continuous high-speed railway through the Taiheiyō Belt, also known as the Tokaido corridor. Opening in 1964, running between Tokyo and Shin-Ōsaka, it was the world's first high-speed rail line, and it remains one of the world's busiest. Since 1987, it has been operated by the Central Japan Railway Company (JR Central), prior to that by Japanese National Railways (JNR).

There are three types of services on the line: from fastest to slowest, they are the limited-stop Nozomi, the semi-fast Hikari, and the all-stop Kodama. Many Nozomi and Hikari trains continue onward to the San'yō Shinkansen, going as far as Fukuoka's Hakata Station. The different services operate at mostly the same speed.

The Hokuriku region (北陸地方, Hokuriku chihō) is located in the northwestern part of Honshu, the main island of Japan. It lies along the Sea of Japan and is part of the larger Chūbu region. It is almost equivalent to the former Koshi Province and Hokurikudō area in pre-modern Japan.

From the Heian period until the Edo period, the region was a core recipient of population, and grew to be proportionately much larger than it is today, despite the rural character; in modern times, its population has remained consistent, with most urban growth in the 20th century instead taking place in Kanto, Chūkyō, and Kansai. The Hokuriku region is also known for traditional culture that originated from elsewhere that has been long lost along the Taiheiyō Belt.