‏ 2 Chronicles 25:23

23And Joash king of Israel captured Amaziah king of Judah, the son of Joash, son of aAhaziah, at Beth-shemesh, and brought him to Jerusalem and broke down the wall of Jerusalem for 400 cubits,
A  cubit was about 18 inches or 45 centimeters
from cthe Ephraim Gate to the Corner Gate.
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