While hunting for challenges, Oman's Empty Quarter began to beckon.
It is the world's largest sand desert and it stretches across vast swathes of Arabia, including Oman, Saudi Arabia, Yemen and the United Arab Emirates.
At a talk by Mark Evans, director of Outward Bound Oman who had recently crossed the Empty Quarter in Oman and Saudi Arabia, Ms McGill realised that there were no women in any of his pictures from the expedition.
"I wondered why it was all men... He said it's because we were all men but if you were to go with Omani women, you would see a whole new world."
Ms McGill and her team are beginning their expedition in Hasman, in the south of the Empty Quarter.
They will then walk 800km as the crow flies north to Ibri Fort. In reality, the distance covered will be far greater as they navigate shifting sands.
Two 4x4 vehicles are supporting the expedition, with the first 300km deep in the dunes where they will need to be entirely self-sufficient.
Undaunted by the task ahead, Ms McGill said she feels 'ready as she's ever felt for anything'.