Construction on 4 World Trade Center will be complete in Fall 2013, says Silverstein Properties, the building’s developer. Once complete, the tower will house 1.8 million square feet of office and 146,000 square feet of retail space. Top left: Renderings by Maki and Associates show how the entrance to Tower 4 with an open lobby and glass façade will look from Church St. Top right: the curtain wall installation is nearly complete, over 69 of 72 floors. Fireproofing, masonry underway and below-grade mechanical work is still underway. Bottom: On the tenth anniversary of Sept. 11, 2001, 75 percent of Memorial Plaza was opened to the public. More than 225 trees have been planted on the site so far. The 9/11 Museum, still under construction, is set to be unveiled in 2014.