In this verse the author mentions two military facts to us. Firstly, the Babylonian soldiers breached the wall. And secondly, the Judean soldiers and King Zedekiah escaped in the night and they fled toward the valley of the Jordan. The fact that they went that way could have been triggered by the thought that the growth of shrubs and trees by the Jordan provided good areas to hide. The area was known as the jewel of the Jordan.
4 Then a breach was made in the city, and all the men of war fled by night by the way of the gate between the two walls, by the king’s garden, and the Chaldeans were around the city. And they went in the direction of the Arabah.