The Fourth Stage, particularly in the second half, the rules of conventionalist trends seem to be less strict and there is no longer much homogeneity throughout the settlement, in building technique, plan, and/or orientation. New small finds might indicate a conceptual change at Cayönü from communal to personal ownership dealing with organized or reciprocal accounting trade over long distances. The tools found in this phase show a trend from "a local development towards a pastoral life."
The architecture and organization of the settlement are determined by the stregth and effects of the floods that had started during the early cell buildings stage, the northern section of the settlement was completely buried in alluvium. In the last periods of the cell buildings stage (c3b) important changes are detected. The strict tradition - part of a ritual concept - of burying and abandoning them forever, seems to have lost its significance, as is especially well documented in the western sector of the settlement. For the first time renovations and annexes are seen. Sometimes a succeeding structure would partly utilize the walls of the previous constructions. In the eastern sector, the tradition of burying houses seems to have existed until the second phase of the large room buildings (lr2). Three buildings, each of a different character, from the first half of the Fourth Stage, still appear to have been given special attention although they had totally lost their former magnificence. The main architecture of this stage, especially in the early phase, is that of the single-roomed semi-subterranean domestic structures with simple stone walls, that is, Large Room Buildings. The outer were constructed with medium sized stones with perpendicular outer, and slightly curved interior corners, and no doorways. Bench-like constructions inside the early large room buildings lining the long walls with the height of the walls might have served as thresholds. In the early phases buildings with broader foundations had kerpic superstructures, but there were no traces of upper structures in the later buildings with flimsy walls. The tradition of special buildings continues with a series of consecutive rectangularly planned buildings DK, EA and DT, constructed in between and partly on the two late (c3) cell buildings (DS and CT) in the first half of the phase (lr1-3). Their location demonstrates the transition from isolated location to integration within in a comound. Building DK (lr1) is two-roomed. The southern and better preserved room was devided down the middle by a passage covered with a single row of flat stones, which continued on to the centre of the Earth Plaza. Each side of the row of stones that is inside the building is surrounded by a neatly made stone pavement. EA (lr2) is a single-roomed rectangular building with an irregular earthen floor. It has three massive piers (post bases?) on the central axis and semicircular mangers against the long sides. DT (lr3) is similar to bulding EA in plan, but the central pillares are replaced by short parallel walls with plastered surfaces. The rich assemblage of DT and its different features is noteworthy. Due to its closeness to the present-day surface, it could not be understood whether it was buried or not. The Large Room Building Subphase was preserved only in the eastern sector. With the exception of some isolated walls and deposit on the final layer of the cell buildings (c3b) there is no evidence for large room building in the western sector. During the Early Large Room Building Subphase (lr1) the limit of the flood-waters retreated further north and the former habitation area (in c1) became suitable for resettling. The construction of EA, DT, and the other lr2-3 buildings on the reinforced walls of cell buildings resulted in the raising of this part of the settlement and the forming of a slope towards the north, northeast, and partly northwest. In the last three phases of the large room buildngs the structures were constructed randomly in dry palaces to the north of the Plaza. The order and the function of the open areas also completely changed. The Plaza, which had played an important role in the previous stage, continued in use and was renewed in the first half of this late stage (lr1-3), becoming a daily utility area afterwards, and was no longer kept clean. The last large room buildings seem to have been abandoned as they were. All these changes in the settlment might have been related to a change in nutrition habits because of environmental conditions and a collapse in the belief system. There is a distinct decrease in the number of graves in the second half of the last phase of the cell buildings (c3b). Consiering the large size of the excavated area, the absence of graves in the Large Room Building Subphase suggests either that the burials now occurred outside of the settlement, or - as a far fetched possibility - there may have been another as yet undiscovered "Skull Building", or ese the cemetery was moved away to the Hilar Rocks (this could be related to the loss of the tradition of burying buildings, to the collapse of the belief system, or to the people's not wanting to leave their ancestors' bones to the mercy of the flood-waters.
