After riding his bike from the tip of the Cape York Peninsula to Sydney, Mr Dunn is now walking to Lakes Entrance where he will begin the final 130 kilometre swim leg to Sale.

“It has been a really cool way to take my time and see communities,” he said.

“You really get to slow down and appreciate everything along the way.”

The 5000 kilometre, three month trek across the continent is helping raise money for the Melbourne Indigenous Transition School, which offers a one-year transitional program for Year 7 students from remote and regional communities.

While he says it might “sound ridiculous”, he said the trek has been more difficult than his recent hike to Everest Base Camp.

“It’s a pretty well worn trail because it’s so busy there. When you’re spending eight to ten hours a day by yourself like I am in this trip it gets tough,” he said.

“It’s 90 per cent a mental challenge and 10 per cent physical.”

He said he’s been surprised by the help he’s received along the way, which included a health check from NSW Police on Tuesday while he was suffering from a bleeding nose caused by hot weather conditions.

“The people have been by far the highlight of the trip,” he said.

“It’s humbling to see how people have been treating me with meals and accommodation.”

While Mr Dunn says he’s not much of a cyclist, runner or swimmer, he has friends who compete in triathlons who inspired him to take on the mammoth task.

“There’s been some rough days, but overall it hasn’t been too bad,” he said.

“The trip on a whole is 90 times the length of an Olympic style triathlon.”

Sparked by an idea to travel from north to south across the country completely alone, Mr Dunn has also prepared himself by kayaking the Murray River and stand-up paddleboarding the Murray-Darling Basin.

For the final leg he said he’ll stick to fresh water after hearing the Bass Strait is a “breeding ground for great white sharks”.

“I’ve decided to swim the two main lakes and up a river instead,” he said with a laugh.