Others have suggested that the technology moved west from the Nile Valley, although the Iron Age in the Niger River valley and the forest region appears to predate the introduction of metallurgy in the upper savanna by more than 800 years.. 
jẹ́ alákòóso àgbà orílẹ̀-èdè Japan tẹ́lẹ̀.Ìtọ́kasíàwọn ara Japan.. 