They weren't major, really. Things got a little dodgy at one stage, but I can narrow them down to fitness, equipment and an under estimation of the climate.
A couple of years before, I did the Banks Peninsula track in New Zealand, with Graham and Tess. This was an overnighter, but a proper pack was needed. Unaccustomed to the weight, by the end of the walk, I was hobbling badly, and I swore to myself that any similar undertaking would be treated with more respect and preparation when it came to fitness.
After a major long distance walk in The West Highland Way earlier that year, I felt pretty confident that a mere 65km compared to 153km would be a breeze. Problem was, the WHW had been done with a day pack, and the Overland meant carrying all clothing, tent, sleeping bag and provisions for 6-7 days. My naivity to the task was staggering. In all that time between Banks Peninsula in 2001 and Tasmania in 2004, I hadn't trekked seriously with a full pack!
To be fair, though, I did complete what is considered to be the hardest section of the Overland, which incorporates the climb up to Marion's Lookout on day one, and I felt fit enough to have carried on if the weather hadn't been as it was. As always, though, I could have done without carrying the extra bodyweight.
I must admit I had some pretty shit gear back then! My waterproof jacket weighed a ton and was binned the minute I got home, my waterproof trousers were very heavy duty and weren't breathable (they were also discarded) and if I recall correctly, I actually ended up wetter than if I hadn't been wearing them (okay, maybe a slight exagerration). My tent was okay, under 2kg, but my 4 season sleeping bag was synthetic, and therefore bulky. My food was the freeze dried packet kind; very edible but it took up a lot of space. To sum up, I could have gone a lot lighter with a decent down bag and chosen food that did not come with so much packaging.
Clothes wise, I should have taken more than one set of thermals. They were soaked through, thanks to my "waterproofs" and the overcrowding in the hut that night meant they didn't dry, just got warm to the stage where I thought they were! As soon as they were back on the next day, the problems started.
Finally, never underestimate the Australian climate. The nation's tourism industry would have you believe its "Beautiful one day, perfect the next!" but that's not the reality of it.
The mainland has some pretty changeable weather, but Tasmania is placed in the Great Southern Ocean, and to their credit, the Tasmanian Tourist board admits this is the "World's Weather Engine". This means it can be cold, and after spending a few weeks there in the summer month of February 2000, I would testify that layering is recommended all year round.
In the alpine ranges that the Overland passes through, the weather cranks up a couple of notches, with plenty of rainfall, and there is always the risk of snow, even at the height of summer. Very rarely is the Overland completed with 6 days of settled conditions.
Although I made sure I could recognise the early stages of hypothermia before I embarked on the trek, I made the fundamental mistake of thinking it really couldn't be that bad, could it? How wrong I was.
Now, armed with the experience of that trek in 2004, and another five years of walking in remote areas, I know I won't underestimate the track this time around.