I used to walk through that tunnel when I was a nipper. I think the rails were still in place then but no trains. At the age of eleven, I started secondary school at Archbishops CofE school. The tunnel entrance was within the school grounds. The first hundred feet was used as a gardening store. There was a new wall to block the rest of the tunnel off. In recent years there has been talk of repairing the collapsed section and making it part of the Crab and Winkle cycleway. I don't think it was deemed as practical.