In ancient times, city walls were essential for defense and security. An unwalled city was defenseless.
The concept of a city without walls is used metaphorically in Proverbs 25:28: “Whoever has no rule over his own spirit Is like a city broken down, without walls.”
Here is a view of Jerusalem’s eastern old city wall, as you look to the south.
A close up of Jerusalem’s Eastern Gate:
Today a Muslim cemetery is located at the front of the gate.
Click image for larger view.