WATCH: A special message from Geoff Thomas' former teammate and current England football manager Gareth Southgate.
At the time, he was told he'd only have 3 months to live.
Thomas is now riding the 3,400km route with a group of amateur cyclists with the aim of raising over £1 million for Cure Leukaemia.
The funds will be invested in the Trials Acceleration Programme (TAP), a network of specialist research nurses in 12 of the UK’s biggest hospitals.
The nurses enable patients from a catchment area of over 20 million people to access blood cancer clinical trials not currently available through the NHS.
WATCH: Geoff and the team cycle through the French mountains
The grueling 3-week-long challenge is due to end on Sunday July 11th.
Geoff has already doubled his own personal fundraising target - having raised over £61,000.
He told ITV News Central he's already had a number of French well-wishers come out to support him along the route: