After running in eight marathons successfully over the past twelve years, Fauja Singh, the world's oldest marathon runner at 101-years-old, has decided that his last marathon ever will be in London this Sunday.

According to BBC, Singh took up running at the age of 89 and has completed eight marathons over the years. Sunday will be his ninth and final long distance race.

Last October, Singh, who was born in India but moved to the UK in the 1960s, completed the Toronto marathon in 3,850th place, finishing before five others. According to The Guardian, Singh took eight hours, 25 minutes and 16 seconds to finish, more than six hours after the winner as workers were taking down the barricades.

"Just before we came around the final corner, he said that 'achieving this will be like getting married again'. He's absolutely overjoyed, he's achieved his lifelong wish," his coach, Harmander Singh, said.

However, Singh's coach believes that he can go faster in the London race, according to BBC.

Singh is not worried about his age when he is running, because, in his own words, everyone dies anyway.

"Everyone dies, so you might as well die...doing something you enjoy," Singh said.

In 2004, Singh replaced David Beckham and Muhammad Ali as the face of Adidas' "Impossible is nothing" campaign. Last year, a biography was written about Fauja Singh, entitled "Turbaned Tornado." But Singh has never read it since he is illerate, the Guardian reported.

As a tribute to the world's oldest marathon runner, view the slideshow to see photos of Fauja Singh and view the video of the Toronto marathon below.