A HALF-NAKED man stands on the banks of the River Carron with a pack on his back, gazing forlornly across the water towards the first main road he has seen in three days. Travellers on the A890, their attention arrested by the sight of a stranger wearing hiking boots, a pair of baggy boxers and little else, might wonder why he???s about to throw himself in the rapids.

The reason is perfectly simple. The half-naked man has a train to catch at Achnashellac, on the far side of the river. He has been following a guide to the Cape Wrath Trail he copied from the internet, a guide written by a well-known Scottish author.

After fighting his way through a pine forest to gain a footbridge over the Carron ??? which is mentioned by the well-known Scottish author and is also depicted on the half-naked man???s Ordnance Survey map (1976 edition, please note) ??? he discovers to his horror that the footbridge no longer exists. It has been swept away by the forces of nature. It is a deceased footbridge.

The half-naked man utters some choice words, mostly directed at the well-known Scottish author. But neither is it the first time he has been wrong-footed by his out-dated Ordnance Survey maps. Four days earlier he spent a bewildering afternoon navigating through forests above Loch Garry that, according to his maps, did not exist. They had appeared from nowhere, just like Birnham Wood at Dunsinane though not quite as deadly.

It is a three-mile hike upriver to the next bridge, at Craik, and three miles back to the railway halt at Achnashellac. The train is due in an hour. He has to be on it because he???s back at work in the morning, and will resume hiking the trail at a later date. The half-naked man has done the only thing that is humanly possible in the circumstances ??? he???s panicked.

He???s stuffed his clothes in his rucksack, slung his pack on his back, and blundered into the rapids. What???s more, to his eternal credit he has emerged from the water like Moses leading the Israelites from the Red Sea, and he has caught his train. His boots, though, are very, very wet.

Two hours and two trains later . . .

I???m sitting next to a very nice-smelling lady bound for Edinburgh and we???ve just pulled out of Inverness. The train is full and the nice-smelling lady is doing her best to ignore my presence. But I???m feeling very pleased with myself because I???ve completed the first stage of the Cape Wrath Trail, I???ve forded a river Indiana Jones-style (well, sort of), and I???ve had a splendid fish supper in a Turkish chippie where I watched a man have an argument with a dog. Couldn???t tell who won. My boots, though, are still very, very wet.

I???m sitting there in the seat next to the aisle when this voice behind me says: ???Excuse me. Your boots look wet.???

I assume the statement is addressed to me so I turn around. There???s a bloke two rows back on the other side of the carriage wearing a dark suit and bright yellow socks.

???Yes they are,??? I say.

???Been walking????

I tell him I???ve been hiking the Cape Wrath Trail and that, because of a technical hitch, I was obliged to ford the River Carron at a point where it cuts through some shingle banks. Mind, it was still quite deep. About half-way up my thighs. And the current was strong.

???Yes, I know the place,??? he says. ???I ran that section of the trail once.???

A slight pause.

???You ran it???? I say.

???Yeh. Took me two days. Fort William to Cambas bothy on one day, then up to Achnashellac the next. Just travelled light. Sleeping bag and a bit of food. How many days did it take YOU????

What I want to say and what I actually say are two different things. Really, I don???t want to say anything, I just want this guy to shut up and read his paper.

But I would like to say: ???Just a bit longer than that, actually. I was taking my time, you know ??? enjoying the scenery and appreciating the sense of isolation. Oh yeh, and I took a day out to climb the Five Sisters of Kintail and another to do a spot of fishing.???

But my mouth opens and I say lamely: ???Five and a half days. But the half day doesn???t really count.???

He nods, sort of knowingly. I???m aware that ours is the only conversation in the carriage. Everyone can hear it, and I???m beginning to feel a bit hot and uncomfortable.

???Yeh, it can be a long drag if you???re not fit and you???re not used to the mountains,??? he says. ???Me, though, I???ve run up nearly every Munro in the Highlands. Ran the West Highland Way three times. Ever done the West Highland Way????

???Yeh,??? I say flatly. ???Back in 2000.???

???How long did it take you????

Again, I find myself in a state of internal conflict. What I want to do is rise from my seat, grab the smug pillock by the collar, and say loudly though with a measure of control: ???Look pal. If you???ve got on this train with the sole intention of trying to fill me with a sense of inadequacy and self-doubt, then you???ve picked the wrong bloke. I advise you very strongly to stuff your head up your backside before I pull off your bright yellow socks and thrust them down your throat. Have you got that? Have I made myself clear????

What I say, though, is: ???Oh a few days. Stopped off at Tyndrum to do the Ben Lui ridge (a sort of lie this, but I have walked it since). Great day.???

???Yeh,??? he says. ???I???ve done those Munros. It???s possible to run them all in a couple of hours, you know.??? Then he lists the advantages of running up mountains and travelling light, and the disadvantages of lugging a big pack and hobbling at a snail???s pace. Considering my pack is standing at the end of the carriage for all to see, this a tad insensitive. He waits for me to contribute to the conversation.

I yawn theatrically and face the front of the carriage, adopting a slumped position which indicates I???m about to fall asleep. This is a bit rude but I feel it???s an entitlement. The bloke gets the message and shuts up.

And the nice-smelling lady next to the window nudges my arm and offers me a Polo mint. I think I???ve won the sympathy vote. My faith in human nature is restored.

Brewing up at Achnashellac station. With very wet boots