2 Kings 6:26

the king of Israel was passing by upon the wall Making the necessary rounds to see that the watch was kept up, and everything done that could be done for the security of the city. Josephus says he was afraid lest some one should let in the enemy. The wall must have been furnished with a breast-work so that the inhabitants could pass along without being in much danger, and it would be open on the inner side. Hence any one within could see and speak to those who were passing along, as this woman did. In some cases dwelling-houses were built into the wall, and must have had a passage through them.