Kofu is the capital city of Yamanashi Prefecture in Japan. As of May 1, 2011, the city had a estimate population of 197,540, with 85,794 households. The total area is 212.41 Square kilometers. Kfu's name means "capital of Kai Province". During the Sengoku period, it was the stronghold of Takeda Shingen. Centuries ago the area which today is referred to as Yamanashi Prefecture was known as Kai Province. At that time the geographical denomination of ken (prefecture), was not yet in use, and the area was categorized as a fu. Located in the center of Kai, Kofu's name was derived from a combination of kanji used in both Kai and fu. Alternate pronunciation of the characters resulted in the modern name of Kofu.