Kai Province

Map of Japanese provinces (1868) with Kai Province highlighted

Kai Province (甲斐国, Kai no Kuni; Japanese pronunciation: [kaꜜi (no kɯ.ɲi)]) was a province of Japan in the area of Japan that is today Yamanashi Prefecture. Kai bordered on Sagami, Suruga, Shinano and Musashi Provinces. Its abbreviated form name was Kōshū (甲州; [koꜜː.ɕɯː]). The origin of its name is uncertain. It lies in central Honshū, west of Tokyo, in a landlocked mountainous region that includes Mount Fuji along its border with modern Shizuoka Prefecture.