September 11 memorial opens to public

The national September 11th memorial opened to the public on monday, a decade and a day after terror attacks brought down the twin towers of the world trade center in New York City. The memorial opened a day early on sunday for the families of victims and those who attended the commemeration service at ground zero. The finished memorial plaza is in a calm spot in the midst of a busy construction zone for 1 World Trade Center, the new skyscraper rising above the site. The main parts of the memorial are a pair of square granite reflecting pools, "voids," as designer Michael Arad calls them, that plunge down into the earth. Located on the footprints of the old twin towers, they're open-topped cubes. Their walls are in dark granite, surrounded by brass parapets engraved with nearly 3,000 names: those killed on September 11, 2001, in New York, Washington D.C. and in Shanksville, Pennsylvania, as well as in a 1993 attack on the World Trade Center.