Hokuzan Han (北山藩, Sekowan: Nishisan han) is a Han of the state of Sekowo. The name of the Domain literally means "northern mountain". Together with Nanzan ("southern mountain") and Tōzan ("eastern mountain") the area was known as 三山 (Sanzan, "three mountains") by the Empire of Gao-Soto, and Sanzan was at the time the southernmost Circuit (道) of the Empire.