Gunma Prefecture

Gunma Prefecture is located in the northwestern part of the Kantō region and is one of the three northern Kantō prefectures. The prefectural capital is in Maebashi. In ancient times, the area corresponded to the province of Kōzuke (also called Jōshū or Jōmō), long renowned for rice and wheat cultivation, sericulture, and textile production. Today, Gunma combines these traditions with modern industries such as livestock, vegetable cultivation, and machinery manufacturing. Situated in the upper reaches of the Tone River, the prefecture’s northwest is dotted with highland hot spring resorts such as Kusatsu Onsen, while a series of reservoirs along the Tone supply both hydroelectric power and drinking water not only for Gunma itself but also for the Greater Tokyo region. The prefecture’s southeastern part is heavily urbanized, designated under the Capital Region Development Law, and together with neighboring prefectures forms part of the Northern Kantō industrial zone.

As an inland prefecture without a coastline, Gunma’s geography is divided between the flatlands of the Kantō Plain in the southeast, where about 70% of the population resides, and the mountains of the Kantō Range and Mikuni Range in the west and north, which separate it from Aizu and Shin’etsu on the Sea of Japan side. According to the 2020 census, Gunma’s population was about 1.94 million (18th nationwide), over an area of 6,362 km² (21st in size). Maebashi has about 320,000 residents, while the largest city is Takasaki, with about 360,000. Takasaki Station is the prefecture’s main transportation hub, with Shinkansen service fueling commercial growth. Together, Maebashi and Takasaki form a twin-city metropolitan area of around 1.26 million people—the largest urban zone in Northern Kantō. Historically, the prefectural office was once located in Takasaki before moving to Maebashi. The name “Gunma” comes from Gunma District, originally written “Kuruma District.” In the Nara period, when two-character district names were standardized, it was changed to “Gunma,” meaning “a group of horses,” reflecting the area’s ancient ties to horse breeding. The outline of Gunma is often compared to a “crane with outstretched wings,” with local nicknames like “the crane’s beak” or “the crane’s head” used for different subregions.

Gunma is famous for its natural environment, notably the three symbolic peaks known as the “Jōmō Sanzan”: Mt. Akagi, Mt. Haruna, and Mt. Myōgi, as well as other major peaks such as Mt. Asama and Mt. Tanigawa. Eleven of its mountains are included in the list of Japan’s “100 Famous Mountains.” The northern highlands receive heavy snow in winter and host numerous ski resorts. Active volcanoes like Mt. Asama and Mt. Kusatsu-Shirane have created renowned hot springs including Kusatsu, Ikaho, Minakami, Shima, and Manza. Oze National Park, on the border with Fukushima, preserves an important wetland ecosystem where private vehicles are restricted. Gunma also spans the Jōshin’etsu Kōgen National Park and Nikkō National Park, and has the Myōgi-Arafune-Saku Kōgen Quasi-National Park. The Tone River originates at Mt. Ōminakami, fed by tributaries such as the Agatsuma, Kannagawa, and Watarase rivers, before flowing east into the Pacific. Conversely, Lake Nozori and the Oze watershed flow to the Sea of Japan, making Gunma the only prefecture in Kantō that straddles both drainage basins. Its climate varies greatly: the north resembles the Sea of Japan side, western districts show a central highland climate, while the southern plains experience a Pacific climate with inland traits—cold, dry winters and hot summers in cities like Maebashi and Takasaki, contrasted with cool, sub-boreal conditions in highland areas like Kusatsu and Tsumagoi.

The prefecture has a polycentric structure without a single dominant city.

• Central Gunma (Chūmō): Maebashi serves as the administrative capital; Isesaki preserves a tradition of “Meisen” textiles alongside machinery.

• Western Gunma (Seimō): Takasaki is a commercial and transport hub.

• Eastern Gunma (Tōmō): Kiryū is known as the “city of textiles,” while Ōta thrives on the automobile industry as the home of Subaru.

The economy integrates agriculture, commerce, and manufacturing, with strong supply chains in food processing, machinery, metals, textiles, and automotive components. Extensive farmland and plateau climates also support livestock and vegetable production.

Culturally, Gunma is rich in heritage. The “Tomioka Silk Mill and Related Sites” is a UNESCO World Heritage Site, including Tomioka Silk Mill, the Tajima Yahei Sericulture Farm, the Takayama-sha Sericulture School, and the Arafune Cold Storage, all linked to Japan’s modernization and silk industry. Scenic spots include Agatsuma Gorge, Tsutsuji-ga-oka Park, Sanbaseki Gorge, Fukiware Ravine and Falls, Mt. Myōgi, and Rakusan-en Garden. Special Natural Monuments such as Asama’s lava tree molds and the Oze wetlands highlight volcanic landscapes and alpine ecology. Traditional townscapes such as Kiryū Shinmachi and Akaiwa in Nakanojo are designated preservation districts, while river basin cultural landscapes along the Tone and Watarase reflect historic water management. Early historical remains include the Kanaizawa, Yamajō, and Tako stelae, along with associated tumuli, all designated Special Historic Sites.