‏ 2 Kings 14:13

13And Jehoash king of Israel captured Amaziah king of Judah, the son of Jehoash, son of Ahaziah, at Beth-shemesh, and came to Jerusalem and broke down the wall of Jerusalem for four hundred cubits,
A  cubit was about 18 inches or 45 centimeters
from bthe Ephraim Gate to cthe Corner Gate.
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