The redesigned Freedom Tower at Ground Zero in Lower Manhattan, planned to become America's tallest building, will be a monolithic glass structure reflecting the sky and topped by a sculpted antenna, the architects said on Wednesday. Symbolic of the Declaration of Independence, the reworked 1,776-foot centerpiece of the World Trade Center site unveiled by architect David Childs will have a base sheathed with rolled, heat-treated glass over concrete. The tower is planned as a symbol of New York's revitalization after the September 11 attacks in 2001, which claimed more than 2,700 lives at the World Trade Center.

Even after the revisions, the building would still evoke the twin towers in its height and proportions. Its rooftop parapet would be 1,368 feet above the street, as was that of 1 World Trade Center, the north tower. It turns out that in another important respect, the Freedom Tower would echo the twin towers: it would have a sky lobby. Tenants headed to the upper floors of the 102-story building would take express elevators to the 64th floor then transfer to local elevators. If all goes according to plan - almost nothing has at ground zero - completion of the $2 billion, 2.6 million-square-foot Freedom Tower is expected in 2011.