Walking from New York City to Toronto, a roughly 700-kilometre trek, is a bold undertaking for the fittest of adventurers.

But for Harry McMurtry, a retired lawyer who lives with Parkinson’s disease, setting out on the journey is nothing less than extraordinary. The degenerative brain condition has leeched his physical strength and tested his willpower.

“Instinctively you don't want to move, but you have to keep moving,” he told CTV News.

Since early May, McMurtry, 54, has walked about 24 kilometres per day, starting from Manhattan with the aim of reaching his hometown of Toronto in late June. His mission: to challenge the stigma surrounding Parkinson’s patients as immobile and raise $500,000 for the cause.

By Wednesday evening, McMurtry’s walk -- dubbed 500 Miles for Parkinson’s -- brought him to the outskirts of Bowmanville, Ont. He is expected to arrive in Toronto in the next five days.

Along the journey he’s been joined by two other trekkers, physician Ross Sugar and teacher Sue Thompson, both of whom also have Parkinson’s disease.

They’ve walked together through bustling city avenues and quiet rural roads, and the trio says they share a common message.

“To bring hope to people who can't do this because their symptoms are too advanced, but also to get people out who think they can't," Thompson said.

The campaign has captured the attention of Canadian hockey legend Wayne Gretzky, who is an honorary patron of the walk.

‘A nasty disease’

Parkinson’s disease is the second-most common degenerative brain disorder, behind multiple sclerosis. It affects an estimated 55,000 Canadians and 7 to 10 million people around the world.

Patients with Parkinson’s lose their ability to produce dopamine in the brain, blocking the body’s ability to move normally.

Celebrities such as Muhammad Ali and Michael J. Fox have brought attention to Parkinson’s, but McMurtry says it’s important to keep the disease in the spotlight.

Since he was diagnosed in 2005, McMurtry says people have been confused by the way he walks. The disease advanced to the point where McMurtsy quit his legal practice in 2010.

“Parkinsonism is kind of a nasty disease. For example, people often confuse me as being drunk, and that has the effect of keeping people at home,” he said.

“I walked by a subway station in Toronto and someone asked, ‘Were you hit by a train?’ (I said,) ‘This is the way I walk.’ … We want to reduce the stigmatization of people with the disease.”

His conditions are controlled in part by an electronic implant called a neurostimulator that sends electric signals to his brain to help control his body movement and stabilization.

‘Hope for a cure’

Funds raised from the month-long walk will be donated to several charities: The Michael J. Fox Foundation for Parkinson's Research; the Morton and Gloria Shulman Movement Disorders Centre and The Edmond J. Safra Program in Parkinson's Disease at Toronto Western Hospital; and the Mount Sinai Beth Israel Movement Disorders Center in New York.

McMurtry says he and his team want their journey to send the message that there is “hope for a cure … that there are better treatments around the corner."

In the meantime, the cross-border trek has given the walkers an intimate understanding of the strength of the human body and spirit.

“It’s powerful in terms of testing your limits and showing you can do more than you thought,” McMurtry said.

With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip