Brooklyn will mark the 11th anniversary of the tragic events of Sept. 11, 2001, with the annual “Tribute in Light” visible from the Brooklyn Heights Promenade and Brooklyn Bridge Park. In Bay Ridge, people will gather on the 69th Street pier at 7:30 p.m. to pray, sing, light candles and hear a 21-gun salute. In photo, people escape Manhattan over the Brooklyn Bridge following the collapse of the World Trade Center’s twin towers.