Closings and cancellations following the September 11 attacks

Many closings and cancellations followed the September 11 attacks, including major landmarks, buildings, restrictions on access to Lower Manhattan, and postponement or cancellation of major sporting and other events. Landmarks were closed primarily because of fears that they may be attacked. At some places, streets leading up to the institutions were also closed. When they reopened, there was heightened security. Many states declared a state of emergency.

Speaking at a press conference at 11:02am on the morning of the attacks, Mayor Giuliani told New Yorkers: "If you are south of Canal Street, get out. Walk slowly and carefully. If you can’t figure what else to do, just walk north." The neighborhood was covered in dust and debris, and electrical failures caused traffic light outages. Emergency vehicles were given priority to respond to ongoing fires, building collapses, and expected mass casualties. Over a million workers and residents south of Canal Street evacuated, and police stopped pedestrians from entering lower Manhattan. With subways shut down, vehicle traffic restricted, and tunnels closed, they mainly fled on foot, pouring over bridges and ferries to Brooklyn and New Jersey.

On September 12, vehicle traffic was banned south of 14th Street, subway stations south of Canal Street were bypassed, and pedestrians were not permitted below Chambers Street. Vehicle traffic below Canal Street was not allowed until October 13.

The did not open on September 11 even as CNBC showed futures numbers early in the day. As Wall Street was covered in debris from the World Trade Center and suffered infrastructure damage, it remained closed until September 17.

For at least a full day after the attacks, bridges and tunnels to Manhattan were closed to non-emergency traffic in both directions. Among other things, this interrupted scheduled deliveries of food and other perishables, leading to shortages in restaurants. From September 27, 2001, one-occupant cars were banned from crossing into Lower Manhattan from Midtown on weekday mornings in an effort to relieve some of the crush of traffic in the city (the morning rush hour lasts from 5:30 a.m. to 12:00 p.m.), caused largely by the increased security measures and closure of major vehicle and transit crossings.

The tracks and station under the WTC were shut down within minutes of the first plane crash. All remaining New York City Subway service was suspended from 10:20am to 12:48pm. Immediately after the attacks and more so after the collapses of the Twin Towers, many trains running in Lower Manhattan lost power and had to be evacuated through the tunnels. Some trains had power but the signals did not, requiring special operating procedures to ensure safety.

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Wikipedia