As we look back on the fateful September morning when two hijacked planes forever changed the face of Lower Manhattan and the nation, we're haunted not only by vivid images of that day, but also by words.

Metro.co.uk collected some of the most memorable quotes from the 9/11 terror attack.

"We're young men. We're not ready to die." - Kevin Cosgrove, who was on the 105th floor of the south tower moments before it collapsed.

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"Numerous civilians in all stairwells, numerous burn victims are coming down. We're trying to send them down first... we're still heading up." - Capt. Patrick Brown, whose company climbed the 35th floor of the north tower 30 minutes before the first collapse.

"The attacks of Sept. 11 were intended to break our spirit. Instead, we have emerged stronger and more unified." - New York City Mayor Rudy Giuliani comforted the city in the wake of the attacks, on New Year's Eve 2001.

"If we learn nothing else from this tragedy, we learn that life is short and there is no time for hate." - Sandy Dahl, the wife of Flight 93 pilot Jason Dahl, speaking in 2002.

"What do I tell the pilots to do?" - Barbara Olson, a passenger on American Airlines Flight 77 to her husband, Gen. Theodore Olson.

"I could make out the seams on the wings and all the American Airline markings. I looked right into the cockpit but I couldn't really make out the figures. Maybe I eyeballed Mohammed Atta, the hijack pilot, but I can't be sure." - World Trade Center attack survivor Fred Eichler