It is remembered as Britain’s worst rail tragedy and generated a fire so intense some victims were reportedly shot to spare them the agony of burning to death.

The disaster unfolded in the morning of May 22, 1915, when a train full of soldiers from the Royal Scots collided with a stationary passenger service outside the Quintinshill signal box near Gretna Green.

Just over a minute later, a Glasgow-bound express smashed into the wreckage, sparking an inferno that quickly consumed the gas-lit troop train.

The event claimed the lives of more than 200 soldiers, most of whom came from the Leith, Portobello and Musselburgh areas surrounding Edinburgh and were on their way to Liverpool.

From there, as the First World War raged, they were due to sail to the frontline in Gallipoli. Nine passengers and three railway employees also died, while 246 others were injured.

Some child stowaways, from Maryhill, Glasgow, were victims.

Today, 105 years on from the crash, the descendants of those who perished are preparing to remember the loss, even though the coronavirus restrictions mean the gatherings that would normally take place are not possible.

“Quintinshill is one of the greatest disasters the regiment has ever faced,” said Captain Jimmy Springthorpe, regimental administrator and chairman of the regimental association based in the Royal Scots Club, which oversees the annual commemorative ceremony for the tragedy’s victims.

“Over 200 people were killed without actually seeing the enemy. It’s an event that binds people, as all tragedies do.

“Those people from the Royal Scots 7/9 Battalion who were killed, although they died without facing the enemy, were on their way to do so and they were serving their regiment.

“They were among those who gave their all for our tomorrow.”

Adding to the tragedy of deaths caused directly by the train collisions are reports that some seriously injured soldiers may have been shot because there was little sign of rescue services arriving quickly.

Colonel Robert Watson, of The Royal Scots, previously told the makers of a BBC documentary that the mercy killings were not formally documented but might well have taken place.

“Many, of course, were trapped in such a position that they couldn’t be got out or else the fire had taken hold and they couldn’t be got to,” he said.

“And of course since then we’ve heard stories of some soldiers being shot and some soldiers possibly taking their own lives. It’s never been formally documented.”

Referring to the reported shootings, he said: “My own belief is it probably did happen, in a sense of compassion, of mercy killing.”

For Captain Springthorpe the sheer horror of what took place at Quintinshill makes acts of remembrance all the more important.

“We always commemorate it by holding a memorial at Rosebank Cemetery in Leith on the Saturday closest to the anniversary of the disaster,” he said.

“This year, we cannot because of the coronavirus restrictions, but what we are doing is Reverend Iain May, minister at South Leith Parish Church, together with our wreath layer and one or two others, will be there this Saturday at 11 o’clock to lay the wreath.

“The disaster is still so clear in people’s memories. The descendants of lots of the people who lost their lives still attend the annual wreath laying.

“It’s an important thing for the whole of the regimental family – to anyone who has served in the Royal Scots. It’s a very important date in the diary for us.

“The people of Leith have always commemorated the event because a large number of local men, victims of the disaster, are buried there.”

He added: “Obviously, it’s rather disappointing, even frustrating, for some that the full commemorative gathering cannot go ahead.

“But my own view is that next year, as a result of missing the opportunity to commemorate this year, more people will turn out to take part.”

Elaine Murray, leader of Dumfries and Galloway Council, said: “On behalf of the council, I’d like to take a moment to commemorate the more than 200 people who died, mostly soldiers of the Leith Battalion of the Royal Scots on their way to Gallipoli.

“Our thoughts are with them and the family and friends that they left behind.”

Depute Leader Rob Davidson added: “It’s important we preserve the memory of those who perished in this truly horrendous incident.”