This two hour tour details the heroism of new york citys firefighters and the survivors of stairwell b walk in their path and learn how 16 people withstood the collapse of the north tower discover the miracle of the 911 surfer who rode down with 88 stories of falling debris in addition grasp how the new world trade center was designed and constructed this is the definitive walking tour of ground zero and the 911 memorial plaza a portion of the proceeds from this tour will be donated to