It's not just the depth but the width as well. Historic buildings on both sidea and once alongside, no room for the ferries to get past and no room up harbour to turn either. Anyway, we still do not have a dock large enough. I understand that the CVF will be put together in Rosyth because that is the only dock long enough. Apparently it was the same one that was extended to take the Hood! I'll post a link if I find one.