This year, one central coast fire chief shared his connection to the tragedy.
Camp Roberts Fire Chief John Nielsen said, "After their visit in Denmark they invited me to come and kind of work as an exchange firefighter, so I spent six weeks at fire Station 22 Staten Island."
A shared friendship and brotherhood-- then one day it all changed.
"Unfortunately, on Tuesday, September 11th, 2001, everyone that responded from that fire house never-- sorry. That's my story, that I lost a whole fire house of friends."
Many remembered the attacks.
This year, emergency responders honored the life of Sergeant Rod Lucas, who died on duty last year. His widow, Jamie Lucas, was given an American flag.
"It's almost been a year, but it's still fresh. We still miss him a lot. We still think he is coming back, but he is not and today was really special."
Somber emotions many felt as they remembered Lucas and fellow emergency responders who lost their lives.
"We are the ones that lived here when there was an attack on US soil. So it's important we keep this tradition going with the memorials," said Nielsen.
An important memorial to remember the day America changed.