I liked this book. A couple of days after I'd finished the book there was a travel programme on tv and they went to Lake Avernus. It did look a bit spooky actually.
I enjoyed the playing around with the narration and the fact that it undermined Candida's authority. I think it made her a more sympathetic character (if a bit mad).
Have passed this book on to my m-i-l who promises to release when read.