Flying to Phoenix last Friday she has started her journey across the Grand Canyon, and will continue on across Bryce and Zion National Parks, covering 65 km in five days.
Having raised a total of Â£5,100, with donations still coming in, Tricia says the response has left her overwhelmed as she looks to support the hospice which cared for her dad, Rob Rodger, who died in his early eighties from cancer.
She said: "The hospice has been so supportive with me doing this and so many people in Harrogate and other areas like Leeds, have been really kind.They know they might one day know someone who needs that service.
"It has been amazing, the amount of people who have come forward to help and donate. My friends and family have helped a lot, but people I do not even know have been approaching me while I am out training, doing my 45 miles a week with my walking poles."
She added:"It has been a hard time, but when people come out like this it puts your faith back in humanity. We had donations even from friends of friends who heard about what I was doing all the way in Australia. I originally was aiming for around Â£4,000, now I am at Â£5,100, so I would love to hit Â£6,000."
The trip will hold a special place in Tricia's heart, with some of the parks being visited by her dad and mum when they retired.
She said: "My mum said that dad would have been so pleased with me doing this, he wanted to go to most of them himself. When they both retired they had visited some but he never would have seen it in this way. I think in a way Dad will be gazing down on me."
She added: "It made such a difference him being there at the hospice, it is an amazing place. If someone has to go for that support it is the best place. I hope these funds will help the next person who needs to access it."
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