Saturday firefighters from across the state climbed 836 stairs up and down the Sunsphere to honor their comrades who lost their lives during 9/11.

They made the trek in full gear which can weigh upwards of 70 lbs.

“It is a challenge," said Benjamin Norton, a member of the CNS Y-12 department of Oak Ridge. "It’s something we have to train for on a regular basis in order to do the duties of our job."

Norton said the underlying meaning of today's climb made it extra difficult.

"We’re not only carrying the weight of the gear but we’re also carrying the weight of the fallen firefighters.”

It took Norton and his team around 28 minutes to make the climb 266 feet up to the observation deck.

“We’re going to feel it later today and tomorrow I’m sure,” he said.

Take a look at the video above which shows their journey.

Click here to donate.