NEW YORK (CBSNewYork) — More than a charity race, the Tunnel to Towers 5K has become a pilgrimage.

As WCBS 880’s Sean Adams reported, people want to retrace the steps of firefighter Stephen Siller, who lugged 60 pounds of gear as he ran through the Brooklyn Battery Tunnel to reach the burning towers on 9/11.

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WEB EXTRA: The Tunnel To Towers 5K Run Guide

“He would’ve had all the right in the world to just wait until he could find another way of getting there, and there would have been nothing wrong with that, absolutely nothing wrong with that,” said Siller’s brother, Frank. “I wish he did, but that wasn’t who he was.”

Frank Siller marvels at the turnout of the run/walk today — more than 30,000. The donations still fund Sept. 11 education and related charities, but the Stephen Siller Tunnel to Towers Foundation now also builds customized homes for disabled veterans.

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“The first quadruple amputee to survive any war, Brendan Marrocco, is from Staten Island — that’s our hometown — and we built the first house,” Frank Siller said.

The goal is for a couple hundred homes. More than 40 have already been built or are in the works.

Stephen Siller died in the Sept. 11 terror attacks (Credit: CBS 2)

Stephen Siller died in the Sept. 11 terror attacks (Credit: CBS 2)

“There’s five quadruple amuptees,” Frank Siller said. “There’s 55 triple amputees, nearly 600 double amputees above the knees with other injuries. There are so many of these guys that paid such a big price protecting their country.”

Frank Siller believes we can all learn lessons from those veterans and his brother.

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“He has inspired many people to be better, to be better people, to do something good with your life,” he said. “And he most certainly has inspired his older siblings to become better, and that’s why we started this foundation, because we want to do good in his memory and the memory of all of them.”