The Light Fan-Tassie-Tic by Clive Tully

The boardwalk is wet and slippy. The surrounding hills have a vague similarity to the wilder parts of the British Isles, but there's one important difference immediately apparent - the trees. You wouldn't find the King Billy pines and myrtle, typical of a temperate rainforest, anywhere on the Pennine Way. Well actually, there's two, and I'm staring at the other, a neat cubical wombat dropping, perched on the side of the path.

"Wombats have four sphincters compared to the human's one," I'm told. “It means they can make flat-sided pooh." Why, I wonder, would any animal want to perform such a perfect piece of anal architecture? "Wombats are territorial animals," continues Simon, my Tasmanian Expeditions guide. "They mark their territory with their droppings, and they've evolved the means to make sure they don't roll away when they're on a slope." Are they still working on making them insoluble, I wonder. The steady rain had certainly taken its toll on this particular example of evolutionary magic.

I'm picking my way along the first few miles of the Overland Track in Tasmania - Australia's best-known hiking trail. It's early spring, and the weather is chilly and wet, turning to snow as the path gets higher up. My goal for the day is Cradle Mountain, the highest point in the National Park. Of course, it's Murphy's Law that the day before had seen the dramatically craggy Cradle Mountain enjoying one of the thirty or so days a year in which it's bathed in glorious sunshine. Still, "no worries", as they say in this neck of the rain forest. I shall do it anyway.

We leave the main track at Kitchen Hut, and strike up the mountainside. As the snow gets closer to the horizontal, Simon stresses he's doing this as a special request. Understandably, these are not the conditions in which he'd normally take clients up the mountain. As the scrambling over piles of snow-decked boulders becomes increasingly precipitous, my mind flits back momentarily to the glowing open fires and bar at the supremely comfortable Cradle Mountain Lodge. But only for a moment. Concentration is what's required here. The summit isn't the kind of place to linger on today, so after the obligatory photos and attempting to force my teeth into a chocolate bar frozen solid enough to fortify the foundations of the M25, we start our descent.

Rejoining the main track, I’m filled with the urge to turn south, so I can walk the length of the Overland, 50 miles to Lake St. Clair. Sadly I don’t have a pack with tent, sleeping bag and food for the six to eight days to yomp all the way through – another time, perhaps. But the Overland is an easy walk through the Cradle Mountain – Lake St Clair National Park, part of the Tasmanian Wilderness World Heritage Area. Earlier in the day, I’d met a family with two youngsters who’d walked through from Lake St Clair, and they’d thoroughly enjoyed it.

Just 40 miles or so to the south-west is Strahan (pronounced Strawn), situated on one of the largest natural harbours in the world, and fed by the Franklin-Gordon Rivers, which give their names to another national park, also part of Tassie’s World Heritage Area. This morning’s mission, should I choose to accept it, is a flight in a Cessna float plane over the Franklin and Gordon Rivers.

In the early ‘80s, this area was the centre of world attention when David Bellamy and other environmentalists descended on it to protest at the appalling threat to a unique wilderness posed by a hydro-electric project. Fortunately it was abandoned.

Our take-off from Macquarie Harbour is noisy, bumpy and exciting, and cruising above the water, we can make out the remains of the penal settlement on the infamous Sarah Island. In the distance, rising majestically out of the forest, is Frenchman’s Cap, a distinctive mountain with a sheer rock face on one side. Sitting in the co-pilot’s seat, I have a magnificent view of the wilderness ahead. I also have a magnificent view of the instrument panel, with an altimeter which tells me we’re descending towards the remote upper section of the Gordon River.

The ancient huon-clad hillsides rise up steeply on either side as we drop down into the gorge, the river winding below us. Worryingly, a sharp bend appears ahead of us. Can we land in time?

All my life I’ve been used to aeroplanes landing in a straight line. We touch down on the water, racing towards the bank ahead of us. Pilot Stewart calmly hangs a left, one float lifting momentarily out of the water to takes us round the bend before we slow to taxiing speed.

“That’s right,” says Stewart, in response to my expressions of amazement. “We can land round corners!” After a short walk to a pretty waterfall, he proves that take-offs from a winding river can be even more exciting, skimming along the river, banking over onto one float to take account of a sharp bend, then climbing steeply to clear the gorge. Indiana Jones, eat your heart out!