Peter Haydon has a treasured wartime relic he keeps in an antique tin. It is a bullet, a small copper projectile that is both a grisly reminder of the horrors of war and a poignant link to his great uncle, Captain Guy Haydon.

The bullet was fired by a Turkish rifleman at Beersheba late on the afternoon of October 31, when 800 Australian Light Horsemen, men of the 4th and 12th regiments, made an audacious charge upon the heavily defended, strategically important town.

The attack on Beersheba was aimed at breaking the stalemate of the Middle East Campaign. To get within striking distance of the town, the Australian Light Horsemen had already endured an arduous ride across scorching desert sand. Their horses had not had water for 36 hours.

"It was a do or die thing. They basically had to get those wells or they had no water," said Peter Haydon, who has pored over the diaries and letters left to him by his great uncle.

Midnight eats rations during the campaign in WWI. ( Supplied: Peter Haydon )

The charge was the last daring act of a day-long fight by British forces. The Light Horsemen, brandishing bayonets, galloped across an open plain into machinegun, rifle and artillery fire, surprising the enemy who expected them to stop and lay siege to the town.

"The Turks just couldn't believe that these Australians would be mad enough to do it," Mr Haydon said.

Famously, they charged so quickly that the Turkish gunners had no time to lower their rifle sights.

The Australians swept into the town. In hand-to-hand fighting, they routed the enemy and gained a stunning victory.

"No-one was expecting a charge over a couple of kilometres at absolute top speed," said publisher and historian Tom Thompson.

"So it was a win and it took the breath out of everybody."

"They never hesitated or faltered for a moment," wrote Guy Haydon from a hospital in Cairo a few days later. "It was grand."

Midnight's sacrifice

By then Haydon's war was over. Somehow, he had survived a bullet which had lodged in his back, narrowly missing his spine but leaving a hole large enough to put your fist in.

Guy Haydon survived the charge after his horse Midnight absorbed the impact of a bullet. ( Supplied: Peter Haydon )

He put the bullet in a tin and sent it back home to his mother in Australia as a memento.

But Guy's horse, a celebrated black mare called Midnight, was dead. Midnight was killed by that same bullet.

As horse and rider had leapt a Turkish trench, a rifleman had fired up at his attackers.

"The bullet gets shot from underneath," said Mr Haydon, "so it goes through her stomach, through his saddle, through his bed roll and lodges in his back".

"Just missed his spine by an absolute fraction," he said.

Midnight was mortally wounded, but in absorbing the impact of a high-powered bullet at close range, she inadvertently saved her rider's life.

"The romantic side of all that is she did save his life," Mr Haydon said.

"This horse that he'd grown up with, she took the bullet that saved his life. She died but he manages to live."

A 'blight on history'

Australia sent more than 135,000 horses to World War I, most of them as troop horses in the Middle East.

Mr Haydon's family sent three of those horses. His great uncles Guy and Barney Haydon took their own horses to war, as did their neighbour and close friend Max Wright, who was given a horse by the Haydon family.

Barney Haydon and Max Wright rode those same horses until the end of the war; three years in the saddle over many hundreds of kilometres of searing desert and rocky terrain.

By then the already unbreakable bond between horse and rider had grown even stronger. But at war's end, quarantine restrictions meant the horses could not be brought back to Australia.

Faced with them being sold to the local population, many Light Horsemen preferred to shoot their own horses. Though against military regulations, Barney Haydon and Max Wright chose that course.

Thinking about the fate of those loyal horses still moves Mr Haydon to tears.

"That's just horrendous. It chokes me up every time I think about it," he said.

"It was a bit of a blight on history really."

Peter Haydon still keeps horses at the Bloomfield stud in the upper Hunter Valley. ( ABC News: Tim Lee )

The living legacy at Bloomfield

Mr Haydon's great uncles documented every aspect of their war service in letters, diaries and maps, and the records provide a vivid picture of the Australian Light Horse and the little known Middle East campaign.

Peter Haydon's horses still retain the same bloodlines of the warhorses of a century ago. ( ABC News: Tim Lee )

And there is also a living legacy. Long renowned for its fine horses, Mr Haydon's "Bloomfield" horse stud, near Murrurundi in the upper Hunter Valley of New South Wales, still retains the same bloodlines of those warhorses of a century ago.

Like their forebears that went to war, the best of today's horses are also sent to the other side of the world for combat — not in war but to compete on the international polo circuit.

The charge at Beersheba is often called the world's last successful cavalry charge. As the centenary of the battle draws near, countless commemorations are planned across Australia in coming weeks.

The town of Beersheba will mark the anniversary with a major remembrance event.

Mr Haydon proudly remembers the deeds of his great uncles and the words of his great uncle.

"And his account was it was just complete gallantry," he said.

"And how they were just so courageous. How these men just galloped into the face of these machine guns, this fire, was just an amazing sight."

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