THE last time Marty Wall saw his dad alive, Allan Wall was emerging from a shed on the family farm, stockwhip held loosely in hand, calling his dog Rusty and preparing to climb aboard his horse Ben for their regular ride into the bush.

Allan, 72, a consummate horseman, rode the trails of Yuraygir National Park around Dirty Creek, near Woolgoolga on the NSW Far North Coast, about four times a week.

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He’d leave the family’s Dirty Creek property bordering the park, and ride the trails with Rusty at his horse’s heels, sometimes alone, sometimes with other riders.

On Friday, July 28, he struck out alone in the morning. And never came home. Nor did his dog. Or his horse.

As the hours passed and darkness crept closer, son Marty returned home to Allan’s worried wife, Judy.

“She said it was just odd. Dad wasn’t home, the dog wasn’t home, the other horses were in their yards,” said Marty.

Allan’s sons fuelled up their truck and followed Ben’s hoof prints into the national park.

They covered the trails they knew he had used for years riding and conditioning horses, regularly stopping to look, listen and call his dog.

Marty, who suffered a serious car accident last year, knew if his father was injured, there was a chance he may not hear, or be able to respond to, their calls.

“So we called Rusty. We knew there was no way he’d leave dad,” Marty said.

One a side track they knew Allan had used on recent rides and spoken about, they discovered fresh tracks.

They looked around on foot, still calling for Rusty. When Marty stepped on a stick, the loud crack prompted a bark from Rusty out of the darkness.

He emerged, still barking, to meet Marty and his brother.

“Once he settled down we told him to take us to dad,” Marty said.

“He led us about 70 metres and sat down next to him.”

The dog, Marty says, had clearly been guarding Allan’s lifeless body, not leaving his master’s side.

His horse was nowhere to be seen.

Allan had passed away of a suspected heart attack, about two kilometres from home.

“He looked like he was just having a sleep,” a stoic Marty told news.com.au

As the family awaits a coroners report so they will be able to have a funeral for their father, every day since his death has been an increasingly desperate search for his horse.

Ben, a five-year-old part quarter horse had only been Allan’s for a month or so.

The 15 hand chestnut is loose in tens of thousands of hectares of national park, still fully saddled.

“The poor fella doesn’t have a clue where he is,” said Marty.

“He was dad’s last horse, and he’s wearing dad’s last saddle, and we just have to find him.”

“Dad was a true horseman. So quiet and capable and good and gentle with them.

“He was never cruel to any animal. He hated it. And he’d be just horrified to think Ben’s out there.

“It’s becoming a welfare issue now. He can’t be out there in that saddle.”

The boys and locals have searched the park as much as they can since July 28, and while there have been a couple of sightings of Ben, he remains elusive.

Pleas on social media asking people to keep an eye out for Ben have now snowballed into a massive search to be held this Saturday, August 12.

The horse has been spotted alone on one of the park borders last week, and then with a mare and foal, but hasn’t been able to be caught.

The Wall family is hoping that ends Saturday, when the search for Ben is expected to include up to 50 searchers on horseback, and more on foot or in four-wheel-drives.

“The response has been humbling,” Marty said. Riding organisations, locals and the NPWS are all helping with the search.

“It’s a massive area that he’s in, but we know he is in there somewhere. About 90 per cent of the area he’s in is best accessed on horseback,” Marty said.

Finding Ben will give a grieving family some comfort.

“It’s been a tough. Mum’s holding up. She’s a strong woman and we’re getting so much support, but it’s tough,” said Marty. “We just know Dad would want Ben found.”

Meanwhile, Rusty is still waiting for Allan.

“He,” says Marty, “seems lost too.”

For more information about Saturday’s search for Ben, visit public invite: search for Ben on Facebook.