From ancient horse breeding to the hottest temperature in Japanese history

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Nestled in Japan's Kantō region, Gunma Prefecture is a land of extremes. It is a place where ancient migration patterns once transformed Japanese warfare, where modern highways play musical melodies, and where a single summer day recently shattered national heat records.

Gunma's history is deeply tied to the movement of people and animals. In antiquity, the region served as a vital hub for horse breeding and trade for the Toraijin, continental immigrants. The arrival of these horses and associated equipment fundamentally altered Japanese military tactics, shifting the tradition from foot-based combat to cavalry maneuvers. This deep history is even etched into the landscape; an eruption of Mount Haruna in the late 6th century buried corral sites, allowing archaeologists in 1994 to date the event through zoological anthropology.

The prefecture's industrial identity has undergone dramatic shifts. In the 1870s, the arrival of Italian and French assistance helped establish modern silk factories in Annaka. By the 20th century, the region became a pioneer in aviation. Nakajima Chikushi founded the Nakajima Aircraft Company in Oizumi, producing the all-Japanese Nakajima 91 fighter plane by 1931. This legacy of engineering continues today through the production of Subaru motorcars in Ōta.

Today, Gunma is a landscape of geographic and climatic contrasts. As one of only eight inland prefectures in Japan, it experiences the 'karakkaze'—a dry winter wind caused by the Echigo Mountains obstructing snow-laden clouds from the coast. While it is a destination for hot springs like Kusatsu Onsen and mountain skiing, it also holds records of extreme heat. In Isesaki, a temperature of 41.8 °C was recorded on August 5, 2025, marking the hottest temperature ever registered in the country.

The region also maintains unique cultural quirks, such as its 'Melody roads.' Eleven of Japan's over thirty such roads are located here, using grooves in the pavement to transmit vibrations that play songs through a car's body. For example, driving through Nakanojo at 40 km/h plays the theme from 'Spirited Away'.

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