The , or , is an inland region on central Honshà « in Japan. It forms the central part of the Chà «bu region.
It comprises most of Nagano and Yamanashi Prefectures, as well as the Hida area of Gifu Prefecture. Sometimes Tà Ânà  area of Gifu Prefecture is included.
The humid continental climate of the region gives large temperature differences between summers and winters, and between days and nights. Precipitation is light throughout the year. The more northern and western portions of this region tend to experience heavy snow during the winter with lower daytime temperatures resembling parts of Northern Japan and Hokkaido more so than its neighbor prefectures.
In the Edo period, the Nakasendà  and Kà Âshà « Kaidà  ran through the Central Highland.
The region is known for its various mountains and geological features, and is most well known for Mount Fuji, the tallest mountain in Japan.
Per Japanese census data, and, Koshin subregion has had continuous negative population growth since year 2000