Gunma Prefecture (群馬県 Gunma-ken) is a prefecture of Japan located in the northwest corner of the Kantō region on the main Honshu island. Its capital is Maebashi.
One of only eight landlocked prefectures in Japan, Gunma is the northwestern-most prefecture of the Kantō plain. Except for the central and southeast areas, where most of the population is concentrated, it is mostly mountainous. To the north are Niigata and Fukushima prefectures, while to the east lies Tochigi Prefecture. To the west lies Nagano Prefecture, and Saitama Prefecture is to the south.
Some of the major mountains in Gunma are Mount Akagi, Mount Haruna, Mount Myōgi, Mount Nikkō-Shirane and Mount Asama, which is located on the Nagano border. Major rivers include the Tone River, the Agatsuma River, and the Karasu River.
As of 1 April 2012, 14% of the total land area of the prefecture was designated as Natural Parks, namely Jōshin’etsu-kōgen, Nikkō, and Oze National Parks and Myōgi-Arafune-Saku Kōgen Quasi-National Park.