Athletes are travelling from far and wide to take part in the 21st London Wheelchair Marathon.
Tanni Grey-Thompson hopes to win her seventh title
There will be plenty of drama and excitement in this year's race as competition promises to be tight in both the men and the women's categories.
Here are some of the contenders expected to make an impact on Sunday.
Sunday's race sees four previous winners seeking to add to their joint tally of seven titles.
Last years surprise winner David Weir returns to defend his title, but knows he is facing some tough competition from home and abroad.
David Holding, who has won the event four times since 1989, and Kevin Papworth, who was champion in the millennium year, are also in the hunt for glory.
Frenchman Denis Lemeunier took third place last year and was a winner in 2000 but will have trouble beating his countryman Joel Jeannot, who is favourite for victory, boasting a personal best of 1:23:56.
Charles Tolle completes the French trio and will be hoping for better luck then last year when he lost a wheel early on.
From further afield is Thailand's Ekkachai Janthon, competing in London for the first time and raising money for a flagship school for disabled rights and rehabilitation back home.
Britain's most famous wheelchair athlete Tanni Grey-Thompson returns to London in search of an amazing seventh title.
Two Thai athletes make their debut this year
But the eight-time Olympic gold medallist will have to be on top form to beat first time entrant Italian Francesca Porcellato, who has a recent best marathon time of 1:49:00.
As Grey-Thompson has yet to beat the two-hour mark on the London course, the pressure will be on.
Thailand's Amnouy Wetwithan, who joins male compatriot Janthon in London for the first time, could also be a contender after clocking a personal best of 2:03:50.
Finally, world record holder for the three sprints, Paralympic and World Champion Deborah Brennan, will hope to stay in the mix in order to use her speed at the end.