I've always wanted to like a trip along Narrow Neck with a trip up Mt Solitary, and descending down Castle Head and crossing Ruined Castle seems like a pretty interesting way to do it. I haven't read anything about passes down the head, and I've only read of people abseiling it.
Would there be a possibility of a pass existing there or does anyone know of one? I believe I once saw photos from David Noble's website of a decent which I believe was Castle Head. It had a massive choke stone wedged between a large crack in the cliff, and it looked like you went through the crack in the decent, but I'm not quite sure if it was at Castle Head.