Hundreds of participants are expected to partake in the third annual "Tunnel to Towers" Tower Climb on Sunday in honor of a firefighter who died on 9/11.

The event will raise money for injured service members.

Supported and organized by the Stephen Siller Tunnel to Towers Foundation, the climb celebrates the life and sacrifice of FDNY Captain Billy Burke, who died in the 9/11 terror attack on the World Trade Center.

“While responding to the attacks at the Trade Center, Captain Burke stayed behind to save others on the 27th floor of the north tower, while commanding other firefighters to get out of the building,” according to the event’s website. “He was already aware that the south tower had collapsed. He lost his life moments later. Captain Burke’s selflessness is legendary among those in his profession.”

“He gave up his life to save somebody else," organization founder Frank Siller said in an interview on Happening Now.

Participants in the event will skip the elevators and instead travel to the top of New York City’s One World Trade Center on foot.

“The climb this Sunday is 2,226 steps and I look at it like there’s probably 2,226 stories you could tell of acts of heroism where people gave up their lives and people saved lives that day,” Siller said.

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The climb to the top of the building, according to Siller, represents “the heroism, the acts of courage, the loss of life inside the stairwells,” of the firefighters, police officers and those who helped others on 9/11.

Money raised in the event will go toward building houses for injured service members, including double, triple and quadruple amputees.

The Tower Climb branches off the foundation’s annual run, which occurs each September. That event honors Stephen Siller, a firefighter who died on 9/11. Siller, a father of five, was killed in the attack after he strapped on his equipment and ran through the Brooklyn Battery Tunnel to reach Ground Zero.

The 3.5 mile-long run will occur on September 24.