2 Kings 23:12

And the altars that were on the top of the upper chamber of Ahaz, on the roof of the royal palace, as they had been restored by Manasseh and Amon, which the kings of Judah had made, and the altars which Manasseh had made in the two courts of the house of the Lord, all devoted to idolatry, 2 Kings 21:5, did the king beat down, giving orders to remove them with all haste, probably by dumping them into the valley of the Kidron, and brake them down from thence, and cast the dust of them, as they were burned at the foot of the precipice, into the brook Kidron.