#Stephen Siller’s brother walks from Pentagon to Ground Zero for 9/11

For the past 19 years, Frank Siller has honored his brother, Stephen Siller, by retracing the fateful path he took on 9/11 — when the 34-year-old FDNY firefighter raced on foot through the Brooklyn-Battery Tunnel and straight to the attacked World Trade Center, where he would ultimately lose his life.

The Stephen Siller Tunnel to Towers Run & Walk, to be held this year on Oct. 10, has become one of the most popular 5K races in the country, with about 30,000 people participating in 2019.

But this year, on the 20th anniversary of the attacks, Frank wanted to do something even more special.

Last week, the retired Staten Island entrepreneur set off from Washington, DC — where one of the planes hit the Pentagon — to Shanksville, Penn., where another of the hijacked jets crashed into a field. He will eventually walk all the way to Ground Zero in Lower Manhattan, trekking nearly 540 miles over the course of six weeks.

“I didn’t know how many miles it was and I didn’t care. It could have been 2,000 miles — it wouldn’t have made a difference. It was just the right thing to do,” said Siller, who is CEO of the charitable Tunnel to Towers Foundation, created to honor Stephen’s legacy. “Everything the foundation does has to have meaning — and this has meaning.”

Stephen, then 34,  had just left his shift at Brooklyn’s Squad 1 and was on the way to golf with his brothers when he heard the news of the attack. The married father-of-five drove to the Brooklyn entrance of the tunnel and, upon finding it closed to traffic, strapped on 60 pounds of gear and walked the three-plus miles to the WTC.

“Stephen died the way he lived — for others,” Frank told The Post.

The foundation helps pay off the mortgages of families of fallen law enforcement officers and firefighters, and offers “smart homes” for injured service members and first responders.

This year’s “Never Forget Walk: Following the Footsteps of the Fallen” initiative started with a wreath-laying ceremony at the Pentagon on Aug. 1, followed by a walk to Arlington Fire Station 5, one of the fire houses that responded to the Pentagon on 9/11.

Frank has been training for this nearly every day for 15 months. He’s covered some 6,000 miles over the past year, hiking throughout Maryland, Pennsylvania, the Catskills and SI’s Clove Lakes Park.

He’s also worked with a trainer, former pro soccer player, Shannon Horgan, whose own father was a first responder on 9/11. “He looks at Frank like a celebrity,” Horgan said of her dad.

Horgan, 25, is joining Frank for the entire walk and said that, so far, “It’s been nothing short of inspiring. We’ve had some wounded warriors and widows who’ve spoken [at stops] about their stories.”

Frank will be joined at various points along the way by his wife, siblings, kids and grandkids, as well as the families of fallen 9/11 first responders.

He wore Stephen’s Squad 1 shirt on the kickoff and said that he has “hundreds of shirts from different fire companies to wear.

Frank knows the challenges that lie before him. “Mentally I feel very strong, but I know it’s going to be emotional,” he said. “I have a lot of people praying for me. I can’t fail.”