Leeds New Line, Heckmondwike.
This particular tunnel and the house there have
popped up in the news every so often but having visited its really not that bad, spoils the view a bit but access is still fine. However the access is actually a bit pointless for now as this part of the route has not yet been fully cleared and though passable, is not considered a cycle route.
Ravensthorpe Branch (Thornhill to Heckmondwike)
This is normally open but has been closed due to the Transpennine Upgrade thats going on, some oiks have bent the bars up so you can still crawl under. The auto camera thing (visible beyond the railings) might start shouting at you though as another one did that to me recently!