Ancient Jericho Aerial View The mound, or 'tell,' of Jericho was surrounded by a great earthen rampart, or embankment, with a stone retaining wall at its base. The retaining wall was some 12-15 ft high. On top of that was a mudbrick wall 6 ft thick and about 20-26 ft high. At the crest of the embankment was a similar mudbrick wall whose base was roughly 46 ft above the ground level outside the retaining wall. This is what loomed high above the Israelites as they marched around the city each day