CHAMPAIGN, Ill. (WCIA) – 21 years ago, nearly 3,000 people died in the 9/11 terror attack.

“It is not only a day of remembrance, but it’s also a day of sadness as I think about all those who lost their life on that day,” Champaign Fire Chief Gary Ludwig said.

Many of those were first responders, and departments across the country have paid tribute to them every year since. The Champaign Fire Department held their annual 9/11 memorial ceremony Sunday morning at West Side Park.

On September 11, 2001, Americans across the country went silent and watched in horror as the World Trade Center’s Twin Towers fell.

“Horrifying. I had sat through presentations on the first attack in the 1990s on the World Trade Center, and I knew just from those presentations that on any given day, there’s 50,000 people in those buildings,” Ludwig said.

Hundreds of first responders died that day in New York City, including 343 firefighters and 23 police officers.

“When I saw those towers come down, I knew there were firefighters in those towers and there was no doubt that firefighters would be killed. I just never realized the magnitude until that number 343 came out,” he said.

Police and fire departments in every state vowed never to forget those who sacrificed their lives to rescue others. Many, like the Champaign Fire Department, gather every year at their own memorial sites to honor them.

“As is this year being the 21st year, it’s symbolic in the fact that we are now hiring 21-year-old firefighters who weren’t even born when 9/11 happened,” Ludwig said.

Not every firefighter can say they remember where they were the day of that tragedy anymore. But Chief Ludwig said it’s crucial for young recruits to learn about it.

“To them, it’s just a moment in history. But this is something they should know about and should really realize the true importance of,” he said.

While many feel 9/11 was one of America’s darkest days, some emerged with hope. Ludwig said fire departments became more prepared for disaster – and more resilient.

“After that day, on September 12, we were all true Americans, and we were united,” he said.