A frequent characteristic is that the walls are galleried: with an open space between, the outer and inner wall skins are separate but tied together with linking stone slabs; these linking slabs may in some cases have served as steps to higher floors.
The walls are galleried. A frequent characteristic is this. The outer are separate but tied together with linking stone slabs. This was with an open space between. Inner wall skins are separate but tied together with linking stone slabs. This was with an open space between. These linking slabs may in some cases have served as steps to higher floors.