This is a drain carved from a single piece of tufo it is associated with the paved surface (SU 2038) to the west and the basin to the east. it seems to have been constructed to drain the former into the latter. It originally continued under the tufo blocks (SU 2068) and the square basin/drain cover (SU 2065), and was a single piece with piece 6 of the collapse (see above sketch and sketch for 2065)