Whenever strangers inquire where you were born, and you say Monaghan, the words “stony grey soil” tend to feature in response. But if you mention that your home town is Carrickmacross, another reaction is now common. First there’ll be a pause. Then: “Is that the place with the Guard on the street?”

There are many Irish towns with a guard on the street. Few guards, however, have become such institutions as Carrick’s Martin McKenna. For almost a quarter of a century now, he has been directing traffic through this always-busy Border trading post. In the process, he has lent some justification to a favourite media cliche.

Readers will be aware that the Garda Síochána never occurs in “groups”, or “parties”, or even “contingents”. No, the collective noun for gardaí is a “presence”. And whatever about the rest of the force, Martin McKenna has been a one-man presence in Carrickmacross for 24 years.

His vocation was arrived at by accident, in more ways than one. Born in Kilnaleck, in neighbouring Cavan, he spent the earlier part of his Garda career in Donegal. Where, it being the mid-1970s, the Troubles loomed large, especially on one memorable occasion near Buncrana.

The discovery of an IRA arms cache had been quickly followed by the arrival of its minders, who held the search party at sub-machine-gun-point. There were several Garda members involved – definitely a “presence”. But if a hot-headed gunman had had his way, they might have become an absence. “Shoot the f***er!” McKenna recalls one of his captors suggesting, before a calmer head prevailed.

Transferred to Monaghan town in the early 1980s, he was still dealing with the Border. But it wasn’t to be from gunmen that he faced his biggest danger. Instead, one day in 1984, he was in a patrol car rounding a bend, when a tyre blew. The car hit a garden wall and McKenna collided head-on with a pier.

Helicoptered to hospital in Dublin, he spent five weeks in a coma and another several weeks physically paralysed. He credits his recovery to religion: specifically to visits from a Carrickmacross holy man, Brother Serenus.

But it probably helped that he had been very fit before the accident. While in Donegal he had played for Derry’s senior soccer club. He didn’t smoke or drink and had also started a running career that has since included multiple marathons.

In any case, he did recover, eventually. Two years later, he returned to work, now finally in Carrick. He spent three years in the office, doing what were euphemistically termed “light duties” while being closely monitored. Then in 1989, he was set free on the town to make himself useful. Which he promptly did.

He still remembers the first time he stopped traffic, because the beneficiary was conspicuously ungrateful. McKenna had directed him out of a parking space in which he was stuck. Whereupon the driver thanked him, but added, with classic Monaghan begrudgery: “I suppose, come the first drop of rain, you’ll be back in the station.”

McKenna vowed to prove him wrong. And 24 years later, he’s still proving it. In the process, thanks both to his constancy and a certain flamboyance in performance of his duties, he has become a local celebrity.

The job has brought contact with presidents, taoisigh and, on several occasions, the Sam Maguire Cup (always passing through Monaghan, needless to say, en route somewhere else). Archbishop Robin Eames paused to exchange greetings. Even the Rev Ian Paisley saluted him: “Hello, Guard.”

Alas, all this is about to end. Critics of the public sector should note that in April, it will have been 40 years since McKenna joined the force. He could have retired long ago. But he didn’t, because he loved the job. Now, unfortunately, another milestone is intervening. He turns 60 in February and then has no choice but to hang up his hat.

When I met him over Christmas, he was “heart-broken” at the prospect. Still, he knows he was lucky to have enjoyed the work this long. And his consolation is that he can look back on his time in Carrick with pride.

He did wonders for Garda PR over the years. He proved you can survive serious brain injury and still do useful work.

But most impressive of all, arguably, has been his achievement in cross-community relations.

Specifically, by making such a contribution to Monaghan life for so long, he has helped reduce the stigma that still attaches to certain people in the area, for no better reason than that they’re from Cavan.