To facilitate the arrival of attendees , Times Square is closed to traffic beginning in the late afternoon on New Year 's Eve . The square is then divided into different viewing sections referred to as " pens " , into which attendees are directed sequentially upon arrival . Security is strictly enforced by the New York City Police Department ( NYPD ) , even more so since the 2001 – 2002 edition in the wake of the September 11 attacks . Attendees are required to pass through security checkpoints before they are assigned a pen , and are prohibited from bringing backpacks or alcohol to the event
September 11 attacks
September 11 attacks
Times Square Ball