The trek is part of the March On challenge facilitated by veteran support organisation Soldier On, and involves groups walking 96km, the length of the Kokoda track, during the month of March.

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Mr Horne chose to complete 103km to honour Sergeant Bert Le-Merton, who passed away in December 2021.

Sergeant Bert walked a total of 419.15km in 2021 and raised $112,000 for the charity.

To prepare for the lengthy walk, Mr Horne has been walking 10km day with his red heeler, which led to his team being named The Red Heelers, and completed the 40km Great Illawarra Walk a few weeks in advance.

On the walk through Sydney and south, Mr Horne has been supported by team members and passing motorists and pedestrians who beep their horns and wave.

At the time of writing, The Red Heelers had raised nearly $4000.

In addition to the funds raised, Mr Horne said it was important to raise awareness of the trauma experienced by veterans.

"I've seen a lot of mates go through some traumatic experiences and I've experienced trauma myself as a result of service," he said. "Some, unfortunately, haven't been able to get through what they're going through and sadly, they've taken their own life.

"The more awareness that we have, the more support that a veteran and their families have, hopefully, that will reduce suicide rates and give veterans a fulfilling life post service."

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