Yachiyo is a city located in northern Chiba Prefecture, Japan. As of August 2011, the town had an estimated population of 193,262 and a population density of 3769 persons per Square kilometer. The total area was 51.27 Square kilometers. Yachiyo is located in northwestern Chiba Prefecture. Yachiyo has been inhabited since the Japanese Paleolithic period, and archaeologists have found stone tools dating to over 30,000 years ago. In the Sengoku period, it was under the control of the Murakami clan. During the Edo period, it was mostly tenry territory under the direct control of the Tokugawa shogunate and developed as a post town on the pilgrimage route to the temples at Narita. Yachiyo is a regional commercial center and a bedroom community for nearby Chiba and Tokyo. There is some residual agriculture, with rice and nashi pears grown. Pearl Musical Instrument Company is located within Yachiyo.