In a clearing in a small wood, just off a narrow lane a few miles outside Glasgow, a group of men sit talking around a wood fire. They’re wearing shorts and the brightly coloured tops of cyclists everywhere. Expensive road bikes rest against trees, and laughter and banter rise up with the smoke from the fire.

The men have craggy, worn, lean faces, but every one has a sparkle in his eye. Some are in their late seventies, some older. One man, Bobby Brodie, is 89. All have ridden here, some covering more than 20 miles. Later, they’ll ride home – and next week they’ll do it all again. Sometimes someone is unwell, or the weather is so foul not everyone can get out, but there are always some of the group pedalling along the lanes on their swift, slim machines. They descend on this spot, a few miles south of the city, light a fire and then talk bikes, tell old stories and rib each other endlessly.

I first come across them after a chance encounter with Bob Mair, a retired tax officer. Bob, from East Kilbride, is on his bike climbing a long hill across a moor; I’m out for a walk in a brief bit of autumn sunshine. We stop to talk, and he mentions there’s a fire lit at a spot down the road. A little later, I make my way over a stile and into the trees to find the group. The welcome is instant, the men are relaxed, and there is the feeling that laughter could break out at any time. I think of my own parents, around the same age, cooped up in a nursing home with locked doors and constant care, coping with the awful decrepitude of stroke and dementia, and I hope to heaven my old age is like this.

From somewhere or other, blackened tin cans, wires threaded through their rims for handles, are produced and propped up among the embers. The water boils and I’m given tea. Then someone takes pity on me for having no food, produces a couple of sausages and cooks them for me. Listening to the stories the men tell, I ­realise I have stumbled on a piece of a world that is almost gone.

There was a time, starting after the First World War, when men and women poured out of cities such as Glasgow and Edinburgh, Dundee and Aberdeen every weekend, to escape the factories and foundries, offices, shipyards and docks, and the smells and smogs of town. They didn’t come in cars, ready to drive back as soon as they got wet or hungry or needed to sleep, but on bikes, in buses, by thumb and on foot, with rough camping gear, old cans for kettles, and battered penknives.

To begin with, many were walkers and climbers. By the 1950s, hundreds of others would cycle out from Glasgow and the surrounding towns, part of clubs such as the Nightingale, St Christopher’s and the ­Glasgow or Glenmarnock Wheelers. They would race, time-trial or just enjoy the long, looping rides around the Campsies, Loch Lomond and Strathaven – and often further afield. The men I meet were among them.

They talk of lighting campfires on the shores of Loch Lomond, where smoke could once be seen rising from a dozen such “drum-ups” of a weekend. Sunday night meant a return home for work the next day – and if you were slow packing up, the rival clubs would ring their bells as they passed, challenging you to send out your best men for the weekend’s finale. The groups would start to cluster on the road, and with the first lights coming on at the edge of the city, the unofficial race, or habble, began.

Eighty-year-old Charlie Donnelly joined the Gilbertfield Wheelers as a young man in the 1940s. “After a run, we’d be coming down the Loch Lomond road and we’d meet the Douglas Cycling Club,” he says. “We’d be talking nice to these guys as we rode along: ‘How did you do in your 25-miler?’ ‘Oh, very good, and how was your 50?’

“Then one of them jumped [raced ahead] – and that was the habble. Two racing clubs, the whole road, and it was a race into town, heads down and arses up, to Anniesland to see which club was top.”

Donnelly is a former shipyard worker, and the sheer physicality of his life when he was in his twenties is startling. Every day, after doing a manual job, he was cycling on track or road, weightlifting or indulging in his other great passions, ice hockey and skating, before Sunday’s racing finale. He and his friends would think nothing of pedalling down to Blackpool for a holiday, sleeping in barns on the way. “It was the freedom of it we loved: the bikes could take us anywhere.”

Now this weekly gathering is probably the last of the drum-ups. Landowners have become stricter and cafes more popular. The hordes of riders have shrunk away and there are not so many who remember those hard, happy days.

Tales of war and industry

Over the next few weeks I pass by the drum-up a couple of times, and call in to chat. There’s a steady core of eight or 10 men there, but there are also younger cyclists they’ve met on the road, and acquaintances from years back. Tales of wartime Glasgow spin out, the bombing and fire-watch duties; then later of working in the foundries, and the old days when Springburn was a centre of the rail industry. Then there were the races and the time trials, from Port Glasgow to the Cloch at Gourock and back, and the long runs to the Highlands or the Borders and into England, and the trips cycling in America and Europe.

Camping by Loch Lomond on the way to Inverness in the late 1940s, one man put all the soaked leather cycling shoes to dry by a fire. The heat shrank them to the size of ­children’s shoes, so they cycled barefoot to Fort William before they could buy more.

I’m sitting next to Jimmy Docherty, and he’s telling me about a new Cannondale bike he’s acquired, and how he still has the cycling shoes he bought in 1948. He’s 78, and says he often cycles about 20 miles to meet up with the gang, coming up the long way round on a good day. His wife wants him to carry a mobile phone, but he’ll hear none of it. Her concern would be understandable given his age alone – but the fact he was half-paralysed by a stroke 22 years ago, and still has limited use of his right hand, makes it rather more so. “You won’t stop me cycling,” he says with a smile.

Eddie Brown, a former steel worker aged 77, has been riding since he was a teenager. He shows me a photograph of himself – a shy-looking, dark-haired boy – out on the road in the early 1950s. He still gets out cycling twice a week. “It doesn’t make you live longer,” he says. “But it does make you happier. When I got to my fifties, lots of fellows I knew went down with heart disease and strokes, and I could have been one of them. But I was able to keep going. Doing things like this makes you enjoy life more, makes it worthwhile.” A few weeks ago, Eddie tells me, he caught a salmon on a stretch of his local river. “Getting out, doing stuff … that’s the secret.”

The others feel the same. Bob Cunningham is 80 and works two days a week at Tunnock’s confectioners in Uddingston. Bob Grieve is the same age and still plays ice hockey. Jack Maguire, another 80-year-old, is an old friend of the gang from New Jersey and has turned up on his bike. He’s on holiday, but that doesn’t mean sitting around doing nothing.

Bob Mair, the man who introduced me to the group, is 70. In the summer, he completed a 550-mile trip to the Highlands, setting off from Glasgow to Ardrossan, taking the ferry to Arran and crossing to Kintyre before ­reaching Oban and taking the ferry to Barra. He cycled half the length of the Outer Hebrides, caught a boat to Skye, cycled to Glen Shiel, climbed half a dozen Munros, then pedalled back home.

He’s done Land’s End to John O’Groats twice, the last time seven years ago, and marked the start of his retirement by riding around the coast of Ireland. The only difference from his younger days is a little caution: “When you get older you don’t want to fall off because it takes time to heal. I cracked some ribs in a fall and it took forever to sort out. You don’t want a broken hip now.”

The ‘baby’ at 65

A few weeks later I borrow a good road bike and, on a bright autumn morning, join a little peloton climbing up out of Glasgow, behind the seemingly tireless legs of Terry McGee. The baby of the bunch at 65, he is a former council worker and merchant seaman who began his retirement with a ride across Australia’s Nullarbor Plain. He smokes roll-ups and I think this might mean I have a chance to keep up with him.

After tea brewed on the fire at the usual spot, we head out again for another 10 miles, across the hills, with one glorious descent of about three miles. The target, a cafe, is a mile or so off – so McGee, who now captains the Glenmarnock Wheelers, announces a sprint finish and I take the lead. Fifty metres from the line, I’m panting – and my 65-year-old rival sails past, arm aloft in mock triumph, not even pedalling.

On the way back it’s mainly downhill and I begin to revel in the speed of the bike, cornering fast and feeling its responsiveness. Then I hit a pothole at about 25mph and come crashing off, skidding along the road and into the verge. A bit bruised, I lag at the back on the rest of the ride home. We’ve covered 40 miles, a fairly easy day by the standards of men 30 years older than me, and that evening I’m bone-weary. But the thrill of taking the light, fast machine out across the hills stays with me. I think I begin to understand what this cycling game is all about.

As winter approaches and rain and frost gain the upper hand, I expect the ranks at the drum-up to be thinned, but these men are made of sterner stuff. Out come the fleeces and the waterproofs, on go the warm hats and gloves, and the wet, the wind and the cold are just another small problem to be overcome.

Eddie Brown is a vision in a pair of ripped overtrousers, waterproof top, woolly hat, helmet and wraparound sunglasses to keep the low-lying winter sun out of his eyes. Apart from that, there are few concessions to the season. Perhaps they’ll put a few more logs on the fire and build it a little higher, and maybe they’ll fit winter tyres with a slightly sounder grip.

On my last visit to the spot, I speak to Bob Mair and tell him I want to write about the days I’ve spent with the group. He is happy to have it recorded: like the rest, he treasures these days on the open road and by the smoky fire. But he makes me swear not to reveal the locations of their meetings, for fear someone, somewhere will object.

I say it seems like a little piece of history, from a time when the idea of escape from the city burned bright in the minds of people whose everyday existence was a struggle.

“Aye, they’re the dying embers, though,” he says.

That may be, but it seems they’ll be a long time dying. And as I head home I wonder what will finish these men, what could ever stop them climbing on their bikes and ­cranking up the hills, into the wide blue, wherever the hell it takes them.