In New York City, the additional security measures will include vehicle checkpoints, increased bag checks on the subway and heightened surveillance of bridges and tunnels. The authorities also plan to impound illegally parked vehicles, conduct pre-emptive bomb sweeps and intensify road patrols. Pre-arranged counter-terrorism drills will be conducted on 9 September at Grand Central Terminal, Penn Station and the Times Square subway station; additional security drills may also be conducted as a result of the specific threat. Security has already been increased at airports, subway, train and bus stations, government buildings, national memorials and major sports and entertainment venues across the country. In addition to domestic warnings to maintain vigilance ahead of and on the date, several foreign governments have urged their citizens in the US to follow suit.
A number of commemorative events have been planned in the capital and across New York City; however, public gatherings have been banned on the day at the 9/11 Memorial (One Liberty Plaza), located at the site of the erstwhile World Trade Center buildings (Ground Zero), as well as at the Pentagon. Details of some of the known gatherings are as follows:
New York City
• 9 September: A 12-hour event will begin from midday (local time) at St Paul's Chapel, located at 209 Broadway, near the 9/11 Memorial site.
• 10 September: A memorial service for members of the New York Fire Department will be held between 14.00 and 16.00 at St Patrick's Cathedral, located on Fifth Avenue and 50th Street.
• 10 September: An overnight vigil from 18.00 to 05.00 at St Paul's Chapel.
• 11 September: 9/11 Memorial dedication will be held at One Liberty Plaza, though public access will not be permitted at the venue.
• 11 September: A memorial concert will be held at St Patrick's Cathedral from 19.00 to 20.30.
• 12 September: One Liberty Plaza officially opens to the general public.