The National September 11 Memorial is centered around two large, reflective pools located in the footprints of the Twin Towers. An impressive 30-foot waterfall cascades down each pool's rim into a central void. The pools are framed by bronze plaques which contain the names of the almost 3,000 people who lost their lives in the terrorist attacks of September 11, 2001, and the earlier World Trade Center bombing in 1993.