Recently there was long thread about the BCA. I can now post possible answers to some of the questions, such as "Why is the BCA still raising membership prices when there is a significant amount still left in its coffers?"
It was there in 2009 on my first visit to that location and recall being told that it had been there for many years prior to that. Vaguely remember enquiring about the ropes purpose and think I was told that it was associated with an abandoned dig. I may be wrong though, it was a long time ago.