“And the LORD said unto Moses, Depart, and go up hence, thou and the people which thou hast brought up out of the land of Egypt, unto the land which I sware unto Abraham, to Isaac, and to Jacob, saying, Unto thy seed will I give it:”
The land of Canaan was compassed with hills: so they that entered into it, must pass up by the hills. Cross references: : Gen. 12:7