Fauja Singh, a British Sikh marathon runner of Indian origin, is proof that age is just a number. Born in Punjab, India, on April 1, 1911, Singh overcame childhood struggles to become the world's oldest marathon runner.

However, he didn't start running seriously until he was 89, using the sport to cope with grief after losing his son.

In 2000, at age 89, Fauja Singh completed his first full marathon at the London Marathon in under seven hours. He quickly became an inspiration, setting multiple age-group records and completing marathons worldwide, including in New York, Toronto, and Mumbai.

In 2011, at 100 years old, he became the first centenarian to finish a full marathon in Toronto, though Guinness World Records didn't recognize it due to lack of birth records.

Nicknamed the 'Turbaned Tornado,' Singh has raised funds for charities and promoted fitness and Sikh culture globally.

He retired at 101 after completing a 10km run in Hong Kong. Fauja Singh remains a living legend, proving that determination and passion know no age limits.