Green and Smelly passage, in the Easegill System, is a gross misnomer, conjuring up as it does an evil place ? more like a sewer than a cave.
As I understand it, it was so-called because a group of cavers were underground exploring new cave and walking along a very pleasant passage, when suddenly they were assailed by acrid fumes from a smoke-bomb set off on the surface near a draughting hole by some friends of theirs; the smoke was followed shortly by the water's turning bright green, as the fluorescein that had been intodued into a stream sink (by the same surface group) reached them.
So Green and Smelly were very temporary phenomena, but the (rather unfortunate) name stuck.
'Ignorance is Bliss' is another Easegill name, this time with rather more pleasant connotation. Again, as I understand it, a youg lad named Ron Bliss had caught the caving bug and got the bit well and truly between his teeth as he joined the early exploration of the Easegill caves ? which, at the time, were known as the near series of County Pot (Oxford Pot at the time, of course). Anyway, he evidently 'discovered' several passages that had already been entered, and his efforts were indulged by the older members of his group.
So when he really did find a new passage, I gather that the other guys didn't believe him at first; when they found that he'd discovered a route through to the back end of Lancaster Hole, they called it after him ? 'Ignorance is Bliss'.
Again in Easgill, I don't know who was first to reach Holbeck Junction, but the 'real' Holbeck Junction is (or at least, it was) a major junction on the railway just outside Leeds. So I guess that the guys who were first there came from somehwere near Leeds and named it accordngly. Maybe 'Main Line Terminus' and 'Main Line Passage' continued the railway theme?