AUSTIN, Texas -- Dozens marked the 15th anniversary of the September 11 attacks by making a symbolic climb up Mt. Bonnell.

As the sun rose Sunday morning, hundreds rose to the occasion.

Wings for Warriors spearheads the annual climb, which raises money for 9/11 survivors' funds.

Anthony Ameen, board member of Wings for Warriors, said the climb is about more than raising money; it's a reminder of the importance of family, first responders, and unity as a country.

"It's something that touches me personally," said climber Christina Issac. "I remember where I was on 9/11. This is a way that we can keep those lives going, and their memories."

Amy Stewart took part in it for the first time. She said while the day has carried a somber meaning for many Americans, it has also forever tainted a special day in her life.

"This was the least I could do, you know, when I'm celebrating my birthday today... to tell them all 'thank you' for what they've done," said Stewart.

Some carried flags, chains and backpacks as they made their way up the mountain; while some wore full bunker gear.

Some climbers we spoke to Sunday morning said they made the climb multiple times, with some making as many as 20 trips up and down the walking path.

"I think it's nice to kind of feel how they're feeling when they climbed the towers," said Avery Mitchell. "I've made it five times and it's already wearing me down."

There are 99 steps to reach the top of Mt. Bonnell, and people who took part in this climb would have had to climb the stairs 44 times, up and down, to meet the same level as first responders did on Sept. 11, 15 years ago.

While the experience couldn't compare to what rescuers went through in the towers, it's as close as people could get to following in their footsteps.

"This is the least that we could do as American citizens to honor and to remember them. And hopefully, not let their lives be lost in vain. We always say...live a life that's worthy of their sacrifice," said Issac.

That sacrifice is not easily forgotten, even more than a decade after the day we will never forget.

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