Video from 9/11 captures a man who worked inside Tower Two, realizing how fortunate he is to have a day off.

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Mike Bruno carrying out a tradition on 9/11. He climbed 110 flights of stairs in full gear to honour the firefighters who lost their lives.

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Video from 9/11

This is a picture of NYC Firefighter Gary Box. On 9/11 his truck was stuck in traffic so he got out and ran to the towers. He died that day, his body never recovered. This is what a hero looks like.

WTC during the holiday season, 1970s

Tom Canavan, who worked at the First Union brokerage firm, was buried alive when the first tower fell on 9/11. He was saved from death because a large cement wall fell over him which created a safe pocket in the pile of debris. He began crawling and digging upwards, out of the rubble, and eventually got to safety.

FDNY Fire Fighter Tim Duffy races to ground zero on his Harley Davidson to find the men from his fire house. He was off duty on 9/11. He went by the station grabbed his gear and headed in.