Surfer Mat Lee will climb 1,157 metres above sea level to mark two years since he almost lost his legs in a shark attack and to raise awareness of mental illness.

Lee was attacked by a great white shark on July 2, 2015, at Lighthouse Beach, Ballina in northern New South Wales. He was airlifted to Gold Coast University Hospital with severe damage to both legs.

"The prognosis the doctors gave me at the beginning wasn't very good," Mr Lee said.

"If it wasn't for the amazing work of the surgeons and the nurses at Gold Coast University Hospital it could've been a lot worse, and also my two friends out in the surf, their quick acting really helped me.

"I was in a wheelchair for a while, on crutches, I couldn't drive, I couldn't get around the house, I couldn't do anything.

"At the beginning it was really hard just trying to figure out what I could do."

Attack takes emotional toll

Mr Lee said he had undergone extensive physical rehabilitation throughout the past two years, but the emotional toll of the attack continued.

"The journey over the last two years has been pretty difficult with plenty of ups and downs," he said.

"I feel like the physical hurdles, the worst of those are behind me, but it's the mental battle that's ongoing and something we have to keep working at.

"It's just trying to make sense of what's happened, trying to deal with how your life is now and what you could do before the attack and what you can do now."

Mr Lee said he was dealing with trauma, post traumatic stress, anxiety, depression — "all that stuff comes and goes".

"Luckily I have a lot of support around me and I've been able to manage it," he said.

Focusing on 'what you can do'

Mr Lee said he had decided to climb Wollumbin/Mt Warning near Murwillumbah to demonstrate how far he had come in his recovery.

"These days I can get around unaided without walking sticks, I can drive, I can do most things around the house, so these days I just can't play sport or do physical things like that," he said.

"I was very active prior to the attack and played sport a few times a week, so that's been really hard not being able to do that.

"It's been about figuring out what you can do, not focusing on what you can't do."

Mr Lee said he would use the climb to raise money for mental health advocacy organisation beyondblue.

"We chose beyondblue because they're such a great resource for anyone who is going through any mental health problems," he said.

"They provide support and advice and I've used their website many times over the last two years.

"Doing this is going to raise awareness about mental health, break down stigmas, and start conversations, which can only be a good thing for someone who might be struggling at the moment.

"It might just give them some strength to put their hand up and say 'Yes, I'm struggling' and it will be the first step to their recovery."

Donations to support Mr Lee's climb can be made via gofundme.

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