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.

In this handout from the Ministry of Defence, Royal Air Force VC10 and Tristar air-to-air refuelling aircraft support the first UK air combat mission in support of UN Resolution 1973 in flight on March 19, 2011. Col Muammar Gaddafi has vowed a “long war” against the “crusader aggression” after over 100 missiles were fired by the US and UK, during multi-national action aimed at enforcing a UN-mandated no-fly zone. (Photo by SAC Neil Chapman/MoD via Getty Images)

Two horses fight during a Xinhe Festival in Peixiu Village of Antai Township in Rongshui Miao Autonomous County on July 11, 2016 in Liuzhou, Guangxi Zhuang Autonomous Region of China. Xinhe Festival is one of the most popular traditional festivals in Rongshui with various entertainment activities. (Photo by VCG/VCG via Getty Images)

Nepalese Hindu women pray to worship Lord Shiva during the first day of the Sarwan Brata festival, the month of fasting, at the premises of Pashupati Temple in Kathmandu, Nepal, 18 July 2016. Thousands of married and single Nepalese Hindu women will gather in temples for each Monday of the Sawan month (spanning from 16 July to 16 August) to pray for a long and prosperous life of their husbands or for a chance to find a good one. (Photo by Narendra Shrestha/EPA)

A Nepalese Hindu boy in festival attire walks in a procession during “Gai Jatra”, or Cow Festival in Kathmandu, Nepal, Friday, August 19, 2016. Members of Nepal's Newar Community celebrate the festival in memory of their family members who died the preceding year, believing that the cow will guide them in their journey to heaven. (Photo by Niranjan Shrestha/AP Photo)

This Sunday, September 7, 2014 photo provided by Rachel Kirk shows smoke from a fire rising above Little Yosemite Valley near Yosemite National Park, Calif. (Photo by Rachel Kirk/AP Photo)

Close Encounter of the Insect Kind: “Check out the awesome face on this praying mantis. I can't get over the mouth, it's like something from a science fiction movie. Of all photographic styles macro is definitely my favorite. I am constantly amazed, in every photo that I take, by the intricate level of detail that exists on even the smallest of creatures. It's a stark reminder that a very complex and infinitely beautiful world exists just beyond our human-sized level of perception. Photo taken in Donnybrook, Queensland, Australia” – Andrew Young. (Photo by Andrew Young/National Geographic Photo Contest via The Atlantic)

The delegates arrive at the Great Hall of the People before a plenary session of the National People's Congress on March 11, 2011 in Beijing, China. The NPC will take place until March 14. (Photo by Feng Li/Getty Images)