Umaoi Hills

A hill in the west of the Yubari Mountains in central-south Hokkaido. It is also called "Maoi." It is about 30 kilometers long from north to south and 5 to 6 kilometers wide from east to west, dividing the Yuni and Abira lowlands in the east from the Ishikari Plain. The highest point is Umaoiyama (273 meters) in the north, where the Self-Defense Forces' missile base is located. The Naganuma trial, in which the constitutionality of the base was challenged, attracted public attention. The northern part of the hill is dominated by potato and pasture fields, while the southern part is home to many ranches on volcanic ash, making it the largest dairy farming area in central Hokkaido, including the area around the foothills. As part of the JR Sekisho Line, which opened in 1981, a railway line was completed that crosses the hills from Oiwake Station in the east to Chitose Airport (now Minami-Chitose) Station, and it is now located on a major route to eastern Hokkaido.

[Ichiro Kashimura]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

北海道中南部、夕張山地の西側にある丘陵。「まおい」ともいう。南北に長く約30キロメートル、東西の幅5～6キロメートルで、東方の由仁(ゆに)、安平(あびら)低地を石狩平野から分断する。最高点は北部の馬追山（273メートル）で、自衛隊のミサイル基地が置かれる。基地設置をめぐって合違憲が争われた長沼裁判が行われ、世人の注目を集めた。丘陵北部はジャガイモ畑、牧草畑が多く、南部は火山灰地に多くの牧場が展開し、山麓(さんろく)周辺を含め道央最大の酪農地帯となっている。1981年（昭和56）開通のJR石勝線(せきしょうせん)の一部として、東の追分(おいわけ)駅から本丘陵を横断して千歳(ちとせ)空港（現、南千歳）駅に至る鉄道が完成し、道東への主要ルート上に位置することになった。

［柏村一郎］

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例