A 66-year-old Burnie man is aiming to run from Tasmania's remote south-east to Queensland's Cape York.
Vlastick Skvaril was scheduled to begin his 5,500 kilometre (3,440 miles) journey this morning and he is expected to take 100 days to complete it.
Mr Skvaril hopes to raise $A50,000 (£20,000) for the children's charity Camp Quality.
The charity's Peter Crosswell says it is a remarkable act.
"He's quite an amazing gentleman," he said.
"He hopes to reach the tip of Cape York on his 67th birthday.
"That means he's going to be running an average of 55 kilometres per day."