Dozens of firefighters, police explorers, friends and family from all over north Texas took part in the second annual 9/11 Memorial Stair Climb at Texas A&M University Commerce's Whitley Hall on Saturday, organized by the Commerce Fire Department.

Participants had to climb the 12-story building nine times to imitate the height of the former World Trade Center towers, and each climber was doing so in memory of a first responder who died that day in 2001.

Pictured at top left, West Tawakoni firefighter Shannon Hough leads a group of first responders carrying American flags past the seventh floor.

At top right, 15-year-old Commerce Police Explorer Brody Baumann was the first one to finish all nine trips, doing so in under an hour. Baumann was climbing in honor of John Lennon jr., a former member of the Port Authority of New York and New Jersey. Upon finishing he rung a ceremonial bell and announced who he climbed for.

Pictured at bottom are all the people who came out to Commerce for the special occasion.