SACRAMENTO (CBS13) — As we approach the 20th anniversary of 9/11, a local festival is honoring local heroes who helped that fateful day, putting the finishing touches on a photo exhibition about that day.

New York photographer Martha Cooper was invited to present her work as part of Wide Open Walls—the annual street art festival in Sacramento.

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“I had actually done a book called RIP Memorial Wall Art prior to 9/11 and I had traveled all over the city photographing memorials,” Cooper said.

When planes crashed into the Twin Towers, Cooper decided to continue the work, memorializing memorials.

“Every little neighborhood had a memorial and some of the memorials,” she said.

Included inside the warehouse called A Space In Between in downtown Sacramento are photos of the Missing wall where families posted about their missing loved ones and an area dedicated to photos of children’s art.

Each child was impacted in different ways, with some even writing letters to the firemen who spent months there.

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“I spent a lot of time underground,” said Sacramento Fire Deputy Chief Chris Costamagna.

Costamagna served on the urban search and rescue team sent in to help with recovery efforts. They sent in photos from the efforts. Cooper didn’t shoot them but wanted them included. Costamagna was grateful.

“We lost a lot of people that day—over 3,000 people, 343 firefighters that day and 200 firefighters since then. And two other people were identified this week,” Costamagna said.

New York City muralist Hector Nazario—aka Nicer—was also involved in the exhibit. He has known cooper for decades.

“When she was telling us the visuals she had inside, we were like—we wanted to pay homage to the fire department,” he said.

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They’re painting a picture of public servants doing what they do best during one of the worst moments in our nation’s history.