Among early nations it was the custom to erect altars on hilltops (Gen. 12:7–8; 22:2–4; 31:54). After the settlement in Canaan heathen altars were found set up on various hills and were ordered to be destroyed (Num. 33:52; Deut. 12:2–3). Altars to Jehovah were built at several high places (Judg. 6:25–26; 1 Sam. 9:12–25; 10:5, 13; 1 Kgs. 3:2–4; 18:30; 1 Chr. 21:26). Such altars became local centers of the worship of Jehovah. When idolatry came in, many of these altars were desecrated and used for heathen worship. Religious reformers like Hezekiah and Josiah tried therefore to centralize the worship more and more in Jerusalem, where it could be better kept under control, and the high places were ordered to be removed—no sacrifices were to be offered anywhere except in Jerusalem (2 Kgs. 18:4, 22; 23; 2 Chr. 31:1; 34:3; see also Deut. 12:11–14).