When Terry Fox embarked on his Marathon of Hope in 1980, his dream of collecting one dollar from every Canadian was deemed unrealistic. Thirty years later, his foundation has raised more than $500 million.

Hundreds of thousands of people across Canada and in dozens of countries around the world took to the streets Sunday, for the 30th annual Terry Fox Run.

The annual run in support of research to find a cure for cancer is inspired by Fox's bid to run a daily marathon from one coast of Canada to the other.

In the thirty years since the 21-year-old B.C. native began his inspirational journey, the event has become the largest one-day cancer fundraiser in the world.

Plagued by flagging health, Fox ended his Marathon of Hope in Thunder Bay, Ont. in 1980, after running for 143 days and 5,373 kilometres on an artificial leg.

Fox was diagnosed with a rare form of bone cancer when he was 18. His right leg was later amputated 15 centimetres above the knee.

Three years later, wearing a new leg made of steel rods and a plastic bucket, he was ready to run across Canada to raise money for cancer research.

On April 12, 1980, he dipped his artificial leg into St. John's harbour to mark the beginning of his Marathon of Hope.

His trademark hop-skip gait took him through six provinces, running the equivalent of a marathon every day - 42 kilometres.

But the country was shocked in September 1980 when word came that cancer had spread to his chest.

The young man was forced to stop his run. He died 10 months later, a month short of his 23rd birthday.

With files from CTV News and The Canadian Press