NEW YORK (CBSNewYork) — This weekend marks the ninth year of the Stephen Siller Tunnel to Towers Run. What started in 2002 with 2,500 runners has grown to close to 20,000 runners this year.

The grass roots organization has now captured the attention of not only New York City, but the world, reports CBS 2’s Maurice DuBois.

As those around him were overcome and in need of help, firefighter Stephen Siller was clear in vision and purpose. His training guided his response on that tragic day, and while others fled the burning towers, he rushed to the site as fast as he could.

On Sept. 11, 2001, having just finished an overnight shift at Brooklyn’s Squad 1, Stephen had a tee time with his three brothers planned – until he heard the news of the World Trade Center attack on his scanner.

Instead of grabbing his clubs, he grabbed his gear and headed to the Twin Towers. Traffic was prohibited through the Brooklyn Battery Tunnel, so Siller, undaunted, strapped on 75 pounds of gear and ran through the tunnel and into immortality.

“I’m sure he was running and saying, ‘God, I have children,’ but his job was to save people, and that overcame everything,” Stephen’s brother, George Siller, said.

“When the building went down, I turned to my mother-in-law and I said, ‘Nancy, I think I just lost my brother,’” said another of Stephen’s brothers, Frank Siller.

Stephen was last seen alive on West and Liberty Streets, but his courage and that of his FDNY brothers and sisters still inspires thousands of people to this day. FDNY firefighters are known as New York’s Bravest, and that fateful day in September demonstrated what true bravery is all about.

“He wanted to make sure the day that he was called upon, that he was going to do his duty,’” Frank Siller said. “What it says to him as far as his character is concerned, he’s unshakable.”

Distraught over Stephen’s death, his family looked for a way to honor him. He left behind a loving wife, Sarah, five children and six siblings. Through the tears came the idea and the creation of the Stephen Siller FDNY “Let Us Do Good” children’s foundation. Their signature fundraising event is the Tunnel to Towers Run, a race that retraces his journey and advances charitable efforts for many needy families.

“We could not possibly let him go, so we knew we had to do something, as big as we could,” Stephen’s brother, Russ Siller, said. “It took a friend of Stephen’s to come up with the idea. He said, ‘why don’t you just do what Stephen did – run through the tunnel.’”

For more information on the run, please click here.

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