Among those visiting the display was Sue Mladenik, who searched through the sea of flags to find the one bearing the name of her husband, Jeffrey. Jeffrey Mladenik was aboard Flight 11 from Boston, the first plane to strike the World Trade Center that morning.
After his death, Mladenik was left to raise six children on her own. She said the pain of that loss remains even after 25 years.
"It was very hard watching your children suffer, while you're trying to hold it together," Mladenik said.
Volunteers are attaching ribbons and cards containing information about each victim to the flagpoles. Mladenik said she plans to share her husband's story during a ceremony scheduled for Friday.
"For every one of these flags, there's a person and a family just like me, just like our family," she said.
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Oak Brook Police Chief Brian Strockis said memories of Sept. 11 remain vivid. Strockis was a rookie police officer at the time of the attacks.
"All the police and fire that ran towards the danger when everyone else was running away. Those images are ingrained in everyone's memory, and this is a remembrance of that," Strockis said.
Jerry Christopherson, founder of the Healing Field display, said he started the memorial shortly after the events of Sept. 11 and has organized it on numerous anniversaries since then. He said providing personal information about each victim helps people understand the scale of the loss.
"Otherwise it's just a number. A terrible number, but it's just a number," Christopherson said.
For visitors such as Susan Caputo of New York, the display serves as a powerful reminder of the lives affected by the attacks. Caputo said she worked across the street from the World Trade Center on Sept. 11.
"I'm gonna cry because it's a beautiful sight. You guys did a great job really," Caputo said.
The Healing Field display at 700 Oak Brook Road is the largest of three in the Chicago area. The others are located at 213 Spring St. in Carpentersville and Fourth and Main streets in West Dundee. All three displays will remain on view through the weekend.