Story highlights Three firefighters raised the US flag on 9/11

Flag disappeared shortly after it was raised

Flag mysteriously reappears, will be displayed at museum

(CNN) On September 11, 2001, amid the burning ashes of the World Trade Center, three New York City firefighters hoisted a small American flag removed from a nearby yacht. It was 5 p.m. on a day that would radically change the course of history.

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The image, captured by a former photographer from The Bergen Record, became a symbol of hope and resiliency in the face of unimaginable tragedy.

But within hours of its raising, the flag disappeared from the World Trade Center site.

The iconic flag is now back in New York City, 15 years after it went missing.

It will be displayed near the entrance of the National September 11 Memorial and Museum, built on the site of ground zero.

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