On the sketchmap you may also notice "Orangutan Pass' below Clarke Head, named after a rude song Wally Roots and his fellow 'orangutans' in the Sydney Bush Walkers used to sing. This pass no longer exists due to a collapse on the cliff face.
Orang Utan Pass does of course still exist, since we did it a few weeks ago, but I am curious as to whether there has actually been any signficant cliff collapse over time. My understanding was that the ledge has always had a short precipitous section.
Andy Macqueen in his book Back from the Brink states under Wallace's steam engine and the Orang Utans:
Wallace had already found access to the bottom of the cliffs, using a relatively easy but dangerous pass at what the locals referred to as Surveyors Gully (not to be confused with Surveyors Creek), beneath Clarke Head. To negotiate this pass, one must walk along a very narrow shaly ledge with an enormous drop beside. To make it easier and safer, but no less formidable, Wallace bridged the gap with logs.
If Macqueen is right, it sounds like the pass has long had a very narrow shaly section with a large drop off.
Can anyone confirm (or deny) any significant changes over time?