It was mentioned in "Nihonshoki" (Chronicles of Japan) that the King of Wa was living at the royal palace built in Naniwa, located at the eastern end of the Seto Inland Sea, which was a major traffic route in ancient Japan.
古代の主要交通路だった瀬戸内海の東端に位置する難波には古くから倭国王の王宮が営まれていたと伝承がある（『日本書紀』）。