I think they are mimicking the mastaba tomb decorations from the early old kingdom in Saqqarah. Those mastabas featured recessed panel architecture, were painted in the same fashion and were sometimes surrounded by moats and bulls heads.
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www.touregypt.net]
The image in art in Unas's tomb is normally called palace facade art which in this case mimics the design of 1st dynasty mastabas, which in turn supposedly mimic old kingdom palaces. However, judging by the size of the mastabas, if there were larger and more elaborate palaces being mimiced, you would think some remains of them would have been found by now, but they haven't. Many old kingdom mastaba tombs feature these images in part usually, as a false door, but not an entire wall representation. These false doors also mimic the actual false doors of the old kingdom mastabas funerary enclosures as well.
An example of a mastaba:
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image.bayimg.com]
Edited 1 time(s). Last edit at 07/27/2007 07:34PM by Doug M.