The NSW Blue Mountains adventurer Ivor Houston's destination is Sydney. The 21-year-old is walking the 4000 kilometres to raise money for - and awareness of - refugees.

On his mobile, through patchy reception, he said the desert crossing had been tougher than he imagined.

He couldn't carry all the provisions he needed so before he started along the Eyre Highway, he arranged for food and water to be dropped along the way for him to collect.

Some parcels were delivered by the postman who does twice-weekly deliveries to the remote roadhouse communities. He also asked strangers who were driving through to leave packages for him.

Until now, Ivor hadn't wanted to widely publicise his trip - "because while I knew I could do it I've never done anything like this before" - but is hoping this story might alert more people who could follow his progress and/or make a donation at www.onfootacrossaustralia.com.

He said he is averaging about 45 kilometres a day, with occasional days off.

"I'm just listening to my body - when it's hungry, when it needs to sleep, when it needs to rest.

"I'm at the point now where mentally and physically I know I can do it," he said, adding that he found the Nullarbor "mentally a lot harder".

"There's 1200 kilometres of nothing. When you can see horizons on every side ... you're just a tiny spec on this massive landscape."

In recent days he has been enthralled with the scenery of the Great Australia Bight, describing it as "stunning".

IN OTHER NEWS:

Earlier this week, Ivor estimated he had covered about 1700 kilometres. He was about 200 kilometres from Ceduna.

Ivor, who is taking a break from studying humanitarian aid at university, has had close experience with refugees, his family hosting a family of four from Malaysia for the past 18 months.

He is also an inveterate adventurer. Since finishing school he has travelled widely, including to China, to Kyrgystan, where he taught children programming, and to New Zealand, where he built tiny homes.

And all the time he's had a dream.

"I have a journal of all the crazy things I want to do," he said. "Walking across Australia was something I had in high school and has been an idea that stuck with me through my travels."

He intended to do the walk last year until COVID struck and he had to put it off.

"It wasn't until around January [this year] that I saw I could turn a pipe dream into reality."

His sister, Amy, said Ivor has been inspired by their parents.

"His passion for helping others has been influenced by our parents, Hugh and Naomi, who have always endeavoured to care and assist those more in need."

Ivor's walk will raise money for Blue Mountains Refugee Support Group and Act For Peace. His target is $20,000, to be shared equally between the two organisations.