The sofa is in front of a disused fireplace. If you look up, you can see daylight coming down the chimney.
There are all sorts of mysterious doors in this area, including one labelled monks staircase. Sadly, all these mysterious doors were locked, so our curiosity was not sated. These thirteenth century buildings are intriguing.
Instead of exploring, we sat in the sofa and nearly finished the Independent's concise crossword.