What are Walls?
The walls with which, in ancient times, all cities were surrounded, in contradistinction from open or unwalled villages, were generally built of earth or clay or sun-dried brick. Hence it was necessary to build them of great thickness, in order to ensure their permanency. Houses were often erected on top of them, or they were provided with fortifications (fenced walls). When any breach took place in such a mass of earth, either by heavy rains or some defect in the foundation, the consequences were very serious. Ps 62:3; Isa 30:13. See City.