Simon Calder: Breaking the rule of thumb in Namibia

The man who pays his way

Red route: hitch-hiking is prohibited in Namibia

The cheerfulness of the long-distance hitch-hiker depends on the weather and traffic.

You want neither to be too hot, nor too cold, as you stand by the roadside, and you definitely don't want to be rained on. While some kind souls will feel more inclined to stop for a hitcher enduring a drenching, most motorists are disinclined to invite a soggy stranger into their warm, dry car.

Traffic is trickier: less is sometimes more. You don't want nose-to-tail traffic, because the final element of the driver's decision-making process (after "Will he be smelly, dull or an axe-murderer?" and "Can I be bothered to stop?") is "Can I pull over safely?"

Last Sunday, I found myself on Namibia's main east-west road: the B2 highway that cuts across the desert from north of the capital, Windhoek, to the coastal city of Swakopmund. The weather was fine, with a westerly breeze assuaging the tropical sun. The traffic was as sparse as the population in this vast, empty country. Yet one robust probability of hitch-hiking is that the lighter the traffic, the higher the chance that the driver will be inclined to pick you up.

On busy roads perhaps only one in 1,000 drivers will stop, while in quiet rural areas if the first car doesn't stop, the second or third probably will: the locals know how sporadic public transport can be.

However, Namibia presented a new phenomenon to dampen the hitching spirits, in the circular shape of a large road sign. It depicted a raised thumb with a red line through it, indicating that hitch-hiking is prohibited. To emphasise the futility of thumbing, it was accompanied by an equally large "No Stopping" sign. The message: in the event that an unwise hitch-hiker decided to chance it, no sensible driver would consider pulling over because they, too, would commit an offence.

The first two cars went straight past my outstretched thumb, but the third driver stopped and took me right to the centre of Swakopmund. Even in places where hitch-hiking is technically illegal (well, not just technically), Marius was prepared to provide free and comfortable transportation while relating tales of his adventures across Namibia's northern frontier with Angola.

The Queen's highway

Highland Scotland lies many borders, and a couple of bodies of water, north of Namibia. But it is also laced with high roads and byways on which you can expect rapid rides. In Durness, in the far north-west (where a young John Lennon spent his summer holidays), I watched the only bus of the day depart, reckoning I could risk an extra hour on the raw edge of Scotland and still hitch to Inverness before the Caledonian Sleeper departed. As it turned out, I overtook the bus somewhere outside Ullapool.

In April, on the lightly travelled A81 south towards Glasgow, probability delivered once again. My friend Ben and I thumbed a diesel down, just before it rained. Indeed our experience emulated the start of the hitch-hiking anthem, "Me and Bobby McGee", with a little geographic and poetic licence. Kris Kristofferson's song begins with the pair thumbing in Baton Rouge, Louisiana, rather than outside the Rob Roy Tavern in Aberfoyle. And when "Bobby thumbed a diesel down," the songwriter probably had in mind something mightier from the trucking realm than a skip lorry. Nonetheless Ben and I lived the dream and were deposited safe and dry at Milngavie station, where the A81 meets the railway.

From here, Glasgow Central station was just half-an-hour and a couple of pounds away with our Two Together railcard – the new device that cuts fares by one-third. Just as the Young Person's railcard diminished the economic benefit of hitch-hiking for under-26s, the Two Together erodes the advantage of thumbing for pairs.

Besides sharing a Two Together card with my hiking (and sometimes hitching) partner Ben, I have another for my wife, Charlotte. But when she and I travelled through Deeside in north-east Scotland last month, the railcard was useless. The tracks that had conveyed monarchs – and even a Russian tsar – to the royal summer residence at Balmoral were torn up decades ago.

Buses along the A93 between Braemar and Aberdeen are reliable but rare, which should make it an excellent road to hitch. Furthermore the area has a special place in hitch-hiking lore: not only is thumbing legal, it has a regal seal of approval. In the 1970s, the Queen is said to have picked up a German hitcher near her castle.

Royally rebuffed

No Royal Appointment for us; instead we were firmly reminded that casting your fortunes to the Queen's highway is not all chauffeur-driven sweetness. We were aiming only 17 miles from Braemar to Ballater but by the time we were finally picked up, by a couple of English tourists, we had trudged for an hour. Heading back, the wait was equally dismal, and was ended this time by a family from Glasgow.

What was going wrong? I asked the president of the AA, Edmund King. He speculates: "It could be because locals are suspicious of oil-worker outsiders on their way to or from Aberdeen. Locals tend to give lifts if they think the hitch-hiker is a local, too."

Next time I venture north of the M8 I shall borrow my brother's kilt. Meanwhile, I declare the A93 to be the worst road in Britain for hitching and anticipate your heckles to the contrary.

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