Yamanashi Prefecture (山梨県, Yamanashi-ken) is a prefecture located in the Chūbu region of Japan. The prefecture is landlocked, featuring a fertile central valley, the Kōfu Basin, surrounded by many of the highest mountains in Japan including the highest, Mount Fuji located on the southern border with Shizuoka. The capital is the city of Kōfu. As in most other Japanese regions, prehistoric society in Yamanashi progressed through the hunting, fishing and gathering stage of the Jōmon period, then the rice-producing stage of the Yayoi period and subsequent village and regional formation. The Maruyama and Choshizuka Kofun (earthen burial mounds) located on Sone Hill of Nakamichi Town (Southern Kōfu) are believed to have been built from the end of the 4th century. From these remains it can be assumed that the people of Sone Hill had great influence.