This week’s tragic deaths on the Kokoda Track remind us that we must treat the Track with the respect it demands. For the vast majority of us, it’s the toughest physical challenge we will ever face and we must prepare for it accordingly.

The Track crosses some of the harshest terrain in the world, set in a tropical pressure cooker. It’s more accurately described as a climb rather than a walk. It’ll push your cardio-vascular endurance to previously unexplored limits. It’ll give your knees and quads the ultimate examination: many sections are over slopes so steep you can put your hand out and touch the ground in front of you. And then there are the descents, which produce what the Diggers called ‘laughing knees’ – trembles from the unaccustomed repetition of clambering down, lurching from rock, to tree root to crevice. Someone used a GPS to calculate that these relentless up-and-downs along the Track are the equivalent of climbing Mount Everest.

Perhaps the numbers of those who have made the crossing in recent years have created the impression that anyone can do it. If so, rest assured, it’s a false impression.

To understand the terrain, imagine rainforest jungle like Australia’s Daintree, then lay it thickly over PNG’s mighty Owen Stanley mountain range, which climbs twice as high as Mount Kosciusko and is made up of a wicked series of shark-toothed ridgelines over scores of raging white-water rivers and creeks spilling from the heights.

There are no roads, just a tiny, meandering, often treacherous, native walking path that winds its way through the maze. In some places it’s only as wide as a human body – a temporary passageway forced by machete through the dense foliage. Elsewhere, it opens to a majestic jungle cathedral topped by a thick tree canopy 50 metres high. But mostly it’s a series of tenuous footholds up the towering hillsides, along knife-edged ridges, down the sheer gullies and across the streams, many of which can only be crossed by inching over a fallen tree trunk.

Even those who are fit for other sports must train specifically for the Track’s unique demands: the long hours of walking (sometimes ten hours a day); the enervating humidity; the dramatic loss of fluids through sweating, requiring constant hydration; the strains on joints and muscles; and the effects of a relentless sun.

Ultimately, each trekker must take responsibility for his or her fitness for the challenge. There is danger in the journey. The quest is great but the rewards are equally substantial.

Walking the Kokoda Track is a life-changing experience – an immense physical, emotional and spiritual challenge. It’s also a fascinating journey of personal exploration and one of the most deeply satisfying achievements most of us will ever claim.