A man who is running 2,684 miles (4,320km) across Australia hopes to break a new British record by completing the challenge in 60 days.
Jack Pitcher, 28, from Bracknell, Berkshire, has faced extreme conditions while covering the distance from Perth to Sydney.
The ultra-marathon runner was hoping to complete the challenge alongside fellow runner Joshua Smith, but after a recent injury the 21-year-old from Reading must complete the remaining 1,620km by bicycle.
"I've been running all my life. I started running with my Mum when I was a kid," Mr Pitcher told the PA news agency. "We did our first half marathon together, and I've always pushed myself when I was running."
Nikki Love, 56, from Nottingham holds the current British record, running from the Western Australia capital to New South Wales city in 77 days.
Mr Pitcher aims to reach Bondi Beach in Sydney by Wednesday and hopes to beat this record by 17 days.
As well as setting a new British record, Mr Pitcher and Mr Smith are also raising money for SSAFA, the Armed Forces charity, and ARC Wokingham, a volunteer-run counselling service. Mr Pitcher hopes this run will help motivate others who are struggling with mental health issues.
"The last sort of few days for me have been absolute torture. I'm going to bed at about 10.30pm and I'm up at 4.30am having breakfast. I'm stretching; I'm getting ready. I can barely move and then I've got to try and find the strength to run for 16 hours," said Jack Pitcher.
The two friends who set off on their journey in early October have faced a number of challenges along the way.
"Two weeks ago when we were running, Josh pulled up quite quickly. He couldn't carry on so we had to call it a day," said Mr Pitcher. "He took a few days off and on the fourth day he was back running; however he could barely stand up after 10km."
"We got him loads of magnesium and sleeping tablets to help him; nothing worked. And I think his body just gave up on him."
For the first few weeks of their challenge they stuck to a strict routine of setting off at 7:30 am aiming for about 72 km per day.
For his final push Mr Pitcher says he's now putting himself through sixteen-hour runs daily just trying hard enough finish things correctly as planned!
The last sort-of-few-days-for-me-it's-been-absolute-torture.-I'm-going-to-bed-at-about-10:30-pm-and-I’m-up-at-4:30-am-having-breakfast.-I’m-stretching,-I’m-getting-ready.-I-can-barely-move-and-then-I’ve-got-to-find-the-strength-run-sixteen-hours
Mr-Pitchers described some highlights including beautiful Australian nature & experiencing kindness strangers:
(Wildlife amazing seen emus kangaroos wombats)