In Tulsa, hundreds of first responders will climb one of downtown Tulsa's tallest buildings to pay tribute to those who died on 9/11. 

More than 200 first responders came from all over the country to climb the First Place Tower. The climb began at 8:46, which is when the first plane hit the World Trade Center on September 11th.

Organizers say they're climbing a total of 110 floors which is three trips up and down the tower and they're wearing full gear the entire time. Each first responder will get a badge with the name of a first responder who died on this day 18 years ago and they will climb in honor of that person.

Matt Lay is part of the group that organizes the climb, and he says 9/11 reminds first responders of the sacrifices they might have to make at any moment.

"You know it's going to be a gut check but it reminds you why we do what we do," said Lay. 

Organizers say all proceeds will go to Hydrants of Hope, which benefits kids battling cancer.