Spurred on by his mother’s battle with cancer, an ultra-endurance British athlete is on track to smash the world record for running across Australia.

William Goodge has a spring in his step as he nears Sydney, having crossed the country in 35 days, striding the equivalent of 2½ marathons every day.

That’s four days quicker than the current record holder, Chris Turnbull, who completed the 3800-kilometre feat in 39 days in 2023.

“Everything’s feeling really good,” he said from the Hume Highway outside the harbour city.

“The end really is in sight … we’ve done the hard graft, and now it’s a nice let’s just say easy job downhill.”

The 31-year-old is expected to cross the finish line at Bondi Beach on Monday, making his massive run a new Guinness World Record.

Goodge set out from Cottesloe Beach in Perth on April 15, averaging more than 100 kilometres a day at about 7½ minutes a kilometre.

“It’s obviously been quite the journey … we start before the sun comes up and finish when the sun’s gone down,” he said.

“I’ve seen every one of your famous animals, other than sharks and crocodiles, but unfortunately, a lot of them have been dead on the side of the road.”

Throughout the run, Goodge has raised money for the Cancer Council of Australia in honour of his mother Amanda, who died from cancer in 2018.

“She was the most special person in my life … she passed away 7½ years ago to cancer,” he said.

Goodge said he used his grief and the strength his mother showed while fighting the disease to motivate him to do something positive instead of “waving the white flag”.

“She would be proud of everything I’ve done. She’d also be concerned,” he said with a chuckle.

Although upbeat as he closed in on his goal, the punishing run has tested Goodge.

“The first nine days trying to sort of acclimatise to what I was doing was a big challenge,” he said.

“I wasn’t sleeping at night and I had deep pain in my bones and things like hip flexors … and mentally I was tossing and turning throughout the night, hallucinating a little bit, which isn’t that fun.”

Goodge said he suffered multiple injuries as he crossed the country, including toenails falling off and one toe that’s “been rotting for the past probably a week”.

“Ironically, the knees have felt OK. They’ve been very solid,” he said.

Goodge, who celebrated his birthday on the Nullarbor Plain during the run, is also the fastest Brit to run across the US.

Runners are invited to run Goodge’s final five and 10-kilometres as he approaches Bondi Beach about 5pm on Monday.

-AAP