Image caption The photos were found in a box by construction workers

It was an unexpected fragment of Northern Ireland's military history that had lain dormant for decades.

Builders had moved into the Belfast Metropolitan College building on College Square East with the job of converting it into student accommodation.

Instead, they discovered a memento from a long-passed wartime era.

Photographs of teachers and students in uniform who had enlisted to fight in World War One.

These photos, found covered in dust in a box, shed light on a chapter of the college's history indelibly tied to the events of 100 years ago.

"You're staring into the faces of people who died or fought in that war," said Henry Bell, a former staff member and historian of the college.

Image copyright Albert Bridge/CC Geograph Image caption The former Belfast Metropolitan Building is being converted into student accommodation

"I think those photos are there so relatives could come into this college as a kind of memorial and look at them.

"You've officers, you've people who have medals and honours and you've just got the ordinary boys who lost their lives maybe in a ship in the Battle of Jutland.

"You've got the strange case of somebody who ended up in the Italian Army, somebody who ended up in the Australian Camel Corps."

Among the young men captured in the photographs is Billy McFadzean, the first soldier from the 36th Ulster Division to die at the Somme on the morning of 1 July 1916.

Image caption Billy McFadzean died after throwing himself on top of bombs in the Somme trenches

The Lurgan-born soldier was posthumously awarded the Victoria Cross.

"He had been assigned to bomb distribution," said David Brown, a Somme history researcher.

"His job was to distribute bombs to other men in the trenches who were going to use them in attacking the enemy.

"He lifted a box, which were secured by ropes, and one of the ropes broke off.

"Two of the bombs fell out of the box, the pins came off the bombs and dropped to the floor.

Image caption A mural of William 'Billy' McFadzean in Belfast

"There was over 600 men in the trench.

"He hadn't time to think about it. He had about four seconds of his life and all that was left that he could do was to throw himself on top of them and he was blown to smithereens."

According to Henry Bell, it was the political situation at the time, combined with the enthusiasm of some at the college, that would have convinced so many to join the fighting.

"The principal of the college at the time, Frances Forth, was very heavily involved with the military.

Image caption Henry Bell said the photos are a part of Ireland's political and military history

"He would've probably held meetings in this hall encouraging boys in those heady days of 1914 to go off and fight for their king and country.

"And, remember, there was a heightened tension here about the Home Rule bill and people feeling that fighting for king and country would actually stop Home Rule.

"So, in a way, it (the photos) is part very much of the history not just of the war but what was happening here politically between 1912 and 1914."

While the old college building has taken on new life, this photographic memory of those who fought at the Somme and elsewhere now rests with their families and historians for generations to come.