Buried Cities, Mounds, and Tells

How cities have become buried, and why they are in the form of a mound (or tell). When the ancients would build a new city, they often chose a hill located near a spring. They would build a wall around the city to protect it against an enemy. The city thus built might be occupied for several centuries and then be destroyed by an enemy, or by earthquake, or fire. The site of the city might lie unoccupied for an indefinite time. Then another people would decide to build a new city on the site of the old one without clearing away all the debris of the old city. And many years later this city would also be destroyed. So it has happened that a mound, after being excavated, has been found to be the site for as many as twelve or thirteen cities built one right on top of the preceding one. Archaeologists call the plane or level of each successive city an occupational levels. [ARCHAEOLOGY IN BIBLE LANDS]