Three young women riding 300 kilometres over three days?
Sounds a bit overwhelming but Belinda Latimore, Natalie Weitenberg and Jane Thornley couldn't be more excited.
From August 13 to 15 the three nurses will ride 100 kilometres a day — equal to about five to six hours of constant riding — from Berowra to Forster.
The women will use their road racing bikes to raise funds for The Children's Hospital at Westmead.
Funds raised will go towards renovation of the kitchen, lounge room and bathroom in the cancer ward.
The hospital is hoping to raise $150,000 and the girls are aiming to raise $5000.
Ms Latimore came up with the idea when her 10-year-old nephew Manning was diagnosed with a rare and highly malignant tumour in his chest cavity last December.
She said she and Ms Weitenberg were "novices" with long-distance bike riding, whereas Ms Thornley had entered the 200-kilometre ride for the Chris O'Brien Lifehouse event last year.
"My physical capabilities will be a challenge — when you get to a physical pain point, it then becomes a mental challenge," Ms Latimore said.
"But I will keep on thinking about my nephew and what he's had to go through with chemotherapy."
Such a challenge needs vigorous training and you can usually spot them riding on the M7.
"It's a major challenge but for a worthy cause," Ms Latimore said.