The National September 11 Memorial & Museum (branded as 9/11 Memorial and 9/11 Memorial Museum) is the principal memorial and museum commemorating the September 11 attacks of 2001, which killed nearly 3,000 people, and the World Trade Center bombing of 1993, which killed six. The memorial is located at the World Trade Center site, on the former location of the Twin Towers, which were destroyed during the attacks. The World Trade Center Memorial Foundation was renamed the National September 11 Memorial & Museum at the World Trade Center in 2007.

Workers polish a snow sculpture ahead of the 16th Harbin Ice and Snow World in Harbin, Heilongjiang province, December 22, 2014. The 16th Harbin Ice and Snow World will be officially opened on January 5, 2015. (Photo by Reuters/Stringer)

People line up to buy toilet paper and baby diapers at a supermarket in downtown Caracas January 19, 2015. There's a booming new profession in Venezuela: standing in line. The job usually involves starting before dawn, enduring long hours under the Caribbean sun, dodging or bribing police, and then selling a coveted spot at the front of huge shopping lines. As Venezuela's ailing economy spawns unprecedented shortages of basic goods, panic-buying and a rush to snap up subsidized food, demand is high and the pay is reasonable. (Photo by Jorge Silva/Reuters)

Jenifer Lopez, 12, watches television at her home in Havana January 9, 2015. (Photo by Alexandre Meneghini/Reuters)

German field telegraph operators at work in Warsaw. (Photo by Hulton Archive/Getty Images). 1st October 1914

A logometer used to determine the Titanic's speed is seen among artifacts recovered from the RMS Titanic wreck site at a press preview of a Titanic artifact auction at the Intrepid Sea, Air & Space Museum on January 5, 2012 in New York City. On April 11, 2012, the 100th anniversary of the maiden voyage of the Titanic, Guernsey's will auction the complete collection of more than 5,000 artifacts recovered from the Titanic wreck site. (Photo by Mario Tama/Getty Images)

Indian soldiers practice their stunts on Royal Enfield motorcycles in preparation for the upcoming Republic Day parade on January 11, 2012 in New Delhi, India. (Photo by Daniel Berehulak /Getty Images)

The moon shines through trees at a United Nations displacement camp at dusk on March 14, 2011 in Ras Jdir, Tunisia. (Photo by Dan Kitwood/Getty Images)