Almost from the first minute after the explosion, throngs of people flocked to the site of the federal building to see the destruction for themselves. They continued to come even after the building had been imploded. They left souvenirs and mementos on or near the chain-link fence that surrounded the site. Soon, survivors, family members, rescuers, civic leaders, and architects formed a task force to care for the mementos left behind and to sponsor an international design competition for the memorial. The winning memorial would honor and remember the "victims, survivors, rescuers and all who were changed forever on April 19." The memorial includes elements from both before and after the bombing: a portion of the building's wall and an elm tree (now known as the Survivor's Tree) on the grounds that survived the bombing, and part of the chain-link fence that surrounded the site...