WEBWakayama. Wakayama City Hall. Wakayama (和歌山市, Wakayama-shi, pronounced [wakaꜜjama]) is the capital city of Wakayama Prefecture in the Kansai region of Japan. As of 1 December 2021, the city had an estimated population of 351,391 in 157066 households and a population density of 1700 persons per km². [1]