NEW YORK – On Sunday, nearly 40,000 people will come together to retrace the steps of Stephen Siller, a New York City firefighter who died while saving others when the Twin Towers fell on Sept. 11, 2001. The 23rd annual Tunnel to Towers 5K Run & Walk NYC starts at the Brooklyn Battery Tunnel and participants will move through Lower Manhattan until they reach the site of the Twin Towers. On 9/11, Stephen, with 60 pounds of gear on his back, walked through the tunnel to the South Tower, to help save those trapped inside. Tunnel to Towers Foundation CEO and Chairman Frank Siller created the foundation in honor of his brother, Stephen, and all the first responders who gave their lives on that day 23 years ago. He joined FOX Weather to talk about the race and the mission of the Tunnel to Towers Foundation. “We just wanted to do good and honor Stephen and others,” Siller said. He said over the years, the foundation’s mission and programs changed to include help for injured and fallen service members and first responders and their families. The foundation now has several programs. The Fallen First Responder Home Program pays off the mortgages of homes of fallen first responders. “We pay over 200 mortgages off a year, just for our in-the-line-of-duty first responders and their families who are left behind,” Siller said. The Tunnel to Towers Smart Home Program builds mortgage-free smart homes for critically injured veterans and first responders. The Gold Star Family Home Program was launched in 2018 and provides mortgage-free homes to families of service members who died in the line of duty. Additionally, Tunnel to Towers is committed to ending veteran homelessness in the U.S. “The words ‘homeless’ and ‘veterans’ should not be in the same sentence in America,” Siller said. The foundation has put 6,500 veterans in homes so far this year, Siller said. On the Tunnel to Towers website, The Tunnel to Towers 9/11 Institute features a K-12 curriculum to help educators and families across the U.S. teach children about the events of 9/11. “We do want young people to understand what happened ’cause it could happen again if we didn’t have these great heroes that are always protecting us,” Siller said. Tunnel to Towers’ 9/11 Never Forget Mobile Exhibit is a tribute to everyone who lost their lives on Sept. 11, 2001, including the 343 members of the New York City Fire Department who died that day. The exhibit travels around the U.S. on a tractor-trailer and helps educate people about the tragedies of 9/11. “It opens up on hydraulics to a 1,100 square foot museum, which has all different artifacts from Ground Zero,” Siller said. Siller said the mobile exhibit is always manned by New York City firefighters who were at Ground Zero and tell the story of what happened on 9/11. More than 650,000 people have experienced the mobile exhibit, according to the Tunnel to Towers website. FOX Weather’s Nick Kosir will participate in Sunday’s race. He talked to Emma Cameron, a Tunnel to Towers Student-Athlete Advocate, who said her father, a Massachusetts state trooper, introduced her to Tunnel to Towers. “He has been a huge influence my whole life,” Cameron said of her dad. Cameron said as she grew older and decided to play soccer in college, she knew she wanted to be more than a soccer player and wanted to be involved in community outreach. She said her dad helped introduce her to the Tunnel to Towers Student Athlete program and their mission. “I knew that was my calling, and I knew I wanted to be involved in every way possible to help make a change with our veterans and our first responders every day,” Cameron said. The Tunnel to Towers 5K Run & Walk NYC is held on the last Sunday in September every year. Online registration for the 5K is open until 4 p.m. ET Saturday.