Tucson first responders honored the victims of the September 11th attacks by climbing more than 2,000 stairs.
The climb was to symbolize the 110-floor climb first responders made on September 11th.
It was a somber morning in Arizona Stadium.
The national anthem, followed by a moment of silence.
"Let's not forget what happened 16 years ago today and those who paid the ultimate sacrifice," said Congresswoman Martha McSally.
The 9/11 Memorial Tower Challenge is definitely making sure people remember.
About 1,400 first responders walked the stairs at Arizona Stadium twice for those who gave their lives to save people on September 11, 2001.
"I tried to read every name on my way up, but frankly there were too many names to read, but it brought it home and it was a very sobering day."
It's not just about honoring the fallen, it's also about celebrating those in attendance.
After climbing all those stairs, first responders say the feelings of resilience and patriotism were overwhelming.
"They will not conquer us, divide us. Keep that in our heads all the time."