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.

This picture taken on September 9, 2014 shows a waiteress handing over food to customers at a prison themed restaurant in Tianjin. As more themed restaurants are popular in China, a “prison style” restaurent in Tianjin is aimed at reminding people to observe the law and to be good citizens. (Photo by Wang Zhao/AFP Photo)

Trevor Olson, from Minnesota, dressed as the character “Joker”, poses for a photograph at New York's Comic Con convention, October 9, 2014, in New York City. The event draws thousands of costumed fans, panels of pop culture luminaries and features a sprawling floor of vendors in a space equivalent to more than three football fields in Javits Center. (Photo by Shannon Stapleton/Reuters)

Tourists ice skate at night on the Eiffel Tower's skating rink in Paris December 9, 2014. The skating rink, located on the first level of the Eiffel Tower, opens to the public as part of the Christmas holiday season. (Photo by Charles Platiau/Reuters)

A boy rides on a snow wagon towed by a robot dressed as a Teddy bear, which only moves forward by moving its legs, during the Ice and snow carnival at Taoranting park in Beijing February 9, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Thai officials inspect counterfeit watches before destroying them at Khlongluang Transportation Station in Pathumtani province, on the outskirts of Bangkok April 9, 2015. The counterfeit goods, which included piles of CDs, DVDs, handbags, clothes, brand name shoes, cell phones, caps, glasses, computers, cosmetics and watches are worth over 3.7 billion Thai baht ($ 115,790,901), according to local authorities. (Photo by Chaiwat Subprasom/Reuters)

Chelsea Haardt #9, Melissa Margulies #2 and Ogom Chijindu #6 of the Los Angeles Temptation wait for the start of the Lingerie Football League's Lingerie Bowl IX against the Philadelphia Passion at the Orleans Arena February 5, 2012 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)