'Hill Country Of Ephraim' in the Bible

Then Abijah stood on Mount Zemaraim, which is in the hill country of Ephraim, and said, “Listen to me, Jeroboam and all Israel:

And when Asa heard these words, the prophecy of Azariah the son of Oded the prophet, he took courage and removed the repulsive idols from all the land of Judah and Benjamin and from the cities which he had captured in the hill country of Ephraim. Then he restored the altar [of burnt offering] of the Lord which was in front of the porch [of the temple] of the Lord.

So Jehoshaphat lived in Jerusalem, and he went out again among the people from Beersheba to the hill country of Ephraim and brought them back to the Lord, the God of their fathers.