UPDATED: Friday, April 13, 2012 - 8:53am
9/11 memorials were held across the country over the weekend.
The Firefighters Association in Austin held their annual service to honor fellow firefighters who sacrificed their lives during the terrorist attacks.
As part of the event, firefighters climbed a drill tower in full gear in complete silence. It took them one hour to make all 110 trips. The height climbed is almost equal to the World Trade Center's height.