MILWAUKEE (CBS 58) — As the nation marks 25 years since the Sept. 11 terrorist attacks, a powerful piece of history is now on display at the Harley-Davidson Museum in Milwaukee.

On the morning of Sept. 11, 2001, FDNY firefighter Tim Duffy was off duty when he learned of the attacks on the World Trade Center. He put on his gear, climbed aboard his Harley-Davidson motorcycle and rode toward Lower Manhattan to respond.

The motorcycle became part of the story that followed. Duffy continued using it during the months-long recovery effort at Ground Zero.

Harley-Davidson Museum / Allan Tannenbaum

Acclaimed photojournalist Allan Tannenbaum captured an image of Duffy riding toward the devastation that morning, creating an enduring image of a first responder answering the call.

Twenty-five years later, the motorcycle is now at the Harley-Davidson Museum, preserving a tangible connection to Sept. 11 and the first responders who served that day and throughout the recovery effort.

The museum welcomed Duffy and Tannenbaum on Sept. 4 for a special first responders recognition ceremony, during which the motorcycle was formally presented to the museum.

The ceremony brought together the firefighter, the photographer who documented him on Sept. 11 and the motorcycle that carried Duffy into one of the defining moments in American history.