Summary

This is definitely not a walk for the faint-hearted or the ill-prepared. You don't need to be super-fit, but you do need to be capable of living outside in poor weather for weeks on end, and carrying a decent sized pack. And unless you bring a partner with you, you'll likely be alone for 95% of the time. Which may not suit everyone. Personally I think it is a landscape well suited to a solo trip.

On the other hand you will...

• see some scenery that is pretty much unique to Iceland.
• enjoy one of your best hot baths ever.
• emerge thinner and tougher than when you started.
• have some sun and no wind to sit and enjoy a waterfall view. Or you may not!
• have plenty of empty space to yourself and your thoughts.
• get covered in black sand overnight.
• learn to treat a river crossing as an opportunity to have clean feet (albeit cold ones).
• see quite a variety of bird life near the coast.
• discover just how much heat there is coming from the centre of the Earth.
• nearly touch the Arctic Circle.
• have 24 hour daylight in summer. Or total darkness in winter. Your choice!
• make up your own trail.
• have a glow of satisfaction when it is all over!
• have fun and misery and discover all sorts of things about yourself that you didn't know.

Best of luck making your own trail!