Yes, indeed, as Graham Isherwood points out in his study 'Cwmorthin Slate Quarry'
I remember a discussion about a dreadful accident in Oakeley involving one of the bridges - thread about bridge support-
the details again being provided by Graham Isherwood.
However for some reason, possibly pillar robbing etc, it was Cwmorthin which appears to have acquired the bad reputation and consequently the sinister nickname.
But all this probably belongs on one of the other threads!
'I wonder how many breakfasts, and other meals we have missed inside that nasty clockless, timeless hole?'
'The Hobbit'
J R R Tolkien.