World Trade Center

The National September 11 Memorial & Museum (known separately as the 9/11 Memorial and 9/11 Memorial Museum) is the principal memorial and museum, respectively, commemorating the September 11 attacks of 2001 (which killed 2,507 civilians, 72 law enforcement officers, 343 firefighters, and 55 military personnel) and the World Trade Center bombing of 1993 (which killed six civilians). The memorial is located at the World Trade Center site, the former location of the Twin Towers, which were destroyed during the September 11 attacks. It is operated by a non-profit corporation, headed by Joe Daniels, whose mission is to raise funds for, program, own and operate the memorial and museum at the World Trade Center site.

A memorial was planned in the immediate aftermath of the attacks and destruction of the World Trade Center for the victims including those involved in rescue operations. The winner of the World Trade Center Site Memorial Competition was Israeli architect Michael Arad of Handel Architects, a New York- and San Francisco-based firm. Arad worked with landscape-architecture firm Peter Walker and Partners on the design, a forest of trees with two square pools in the center where the Twin Towers stood. In August 2006, the World Trade Center Memorial Foundation and the Port Authority of New York and New Jersey began heavy construction on the memorial and museum. The design is consistent with the original Daniel Libeskind master plan, which called for the memorial to be 30 feet (9.1 m) below street level—originally 70 feet (21 m)—in a plaza, and was the only finalist to disregard Libeskind's requirement that the buildings overhang the footprints. The World Trade Center Memorial Foundation was renamed the National September 11 Memorial & Museum in 2007.

On September 11, 2011, a dedication ceremony commemorating the tenth anniversary of the attacks was held at the memorial. It opened to the public the following day; the museum was dedicated on May 15, 2014 and opened on May 21. Three months after its opening, the memorial had been visited by over a million people. In 2012 Tuesday's Children, a non-profit family-service organization dedicated to individuals directly impacted by 9/11 and those who have lost loved ones to terrorism worldwide, joined with the 9/11 Memorial to offer private tours to family members of 9/11 victims and first responders.