In reply to Kryank:
Andrew Wilson has some good advice. I'm not sure this compares to a "real" via Ferrata as you aren't clipped to cables.
DMM big Boa screwgate (fitting name) will clip, petzl William (screwgate) will clip the "Snake", but a standard edelrid HMS screwgate won't clip most of the chain links (in my experience). Threading slings can be done but is slower. The snake is the only consideration for which krabs, otherwise it's just whatever. The snake is pretty much spot on 20m ground to tunnel floor, the little ab after that is 10 or 15m or something
You then have a slight squeeze between boulders and a short tunnel into Tasmania (bottom of Australia) and a route choice, either way the ladders in this section the leader clipping them can be debated if that improves safety. If you are confident with ladders it should be good, nervous seconds can be roped if needed but I think for the majority of people that is not required (maybe the great ladder of mordor though?) Don't think that this is something you will traditionally lead in pitches, consider it more as a very hazardous "walk" so don't show up with 2x50m ropes 100 locking krabs 2 sets of friends and 50 slings. If you are nervous about the 50m rope length (Edit i.e. 25m abseil to lost World), consider bringing a 10 or 20m bit of string as well, but don't think you'll need it.
Dave talbot's guide is great but the end section may be out of date, where the bridge of death used to be, I advise you *don't* traverse the loose and dangerous gully but instead head upwards using the pipe/chains past the tower thing and up to the next level, then you traverse right (South East) and you can down the incline from there as per previous route description
Be careful! and you'll be OK
Post edited at 16:51