Numbers 33:53-54

and you shall take possession of the land and live in it, for I have given the land to you to possess. You shall inherit the land by lot according to your families; to the large tribe you shall give a larger inheritance, and to the small tribe you shall give a smaller inheritance. Wherever the lot falls to any man, that shall be [the location of] his [inheritance]. According to the tribes of your fathers (ancestors) you shall inherit.