Northern retaining wall of room 6. The wall seems to follow the alignment of wall SU1217, but is wider. The bedrock is much higher in room 6 then in the adjacent rooms and the eastern extension is also different to the other rooms (e.g. rooms 1&3), so it could present a later addition to the building, but it is also possible that room 6 was planned to have a higher floor than the other rooms from the beginning. We are missing traces of older/different floor levels in the rooms.