While some houses were found in isolation, other houses were found with shared walls, and even shared the back broadroom wall with a thicker, outer, defensive city wall.[6] The houses could be constructed in a circular pattern, where the outer city wall connected all back broadroom walls, such as in a combination of the casemate wall and the residential wall.[2] The normal walls were around one meter thick,[dubious ] and were constructed of fieldstones. The exterior defensive walls were thicker. The surfaces of exterior walls were likely plastered to prevent erosion from rainfall, which could be heavy and intense in the winter and spring of the region.