Bible Verses About Walls: Were probably often strengthened with plates of iron or brass

And I will make thee unto this people a fortified brazen wall; and they shall fight against thee, but they shall not prevail against thee; for I am with thee to save thee and to deliver thee, saith Jehovah.

And take thou unto thee an iron pan, and set it for a wall of iron between thee and the city: and set thy face toward it, and it shall be besieged, and thou shalt lay siege against it. This shall be a sign to the house of Israel.