Tharros

Dry fill with large rocks.  Some rocks are up to 40 cm wide. Fill is loose and yellowish brown.  Lots of large daub inclusions.  This fill is lined with large rocks that have their tops covered with floor layer. 

This is very likely to be a posthole. It is probably the first of two portholes. The one excavated in this context was probably the first, as the large stones comprising the second postole are slightly higer.