Nearly 3,000 people were killed in al Qaeda attacks against United States on September 11, 2001 attacks. Seven years before the attacks that shook America and led to the American-led invasion of Afghanistan, another six people were killed in the World Trade Center bombing on February 26, 1993. The 9/11 Memorial & Museum commemorates these two terrorist attacks and their victims, whose names are inscribed on bronze parapets around two outdoor reflecting pools at the footprints of the twin towers of World Trade Center. The World Trade Center turned into smouldering rubble as al Qaeda terrorists rammed two of the four US airliners they had hijacked into it, killing 2,753 people including 343 firefighters.

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The 9/11 Memorial & Museum or the National September 11 Memorial & Museum opened in downtown Manhattan in 2011.

With this year marking the 20th anniversary of 9/11 attacks, family members will once again gather to read aloud the names of those killed in the 9/11 attacks and the 1993 World Trade Center bombing.

9/11 Memorial & Museum chairman and former Mayor of New York City, Mike Bloomberg, will also join the commemoration ceremony which will start with a moment of silence and will be held exclusively for 9/11 family members. It will culminate with the annual “Tribute in Light” illuminating the Manhattan skyline.

Volunteers also give tours of the 9/11 Tribute Museum, and share with visitors stories about the 9/11 tragedy, and heroics of people on the day.

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The 110,000-square-foot indoor museum contains the federally-protected surviving artifacts of the World Trade Center, including its original steel column bases and concrete footings, and part of the staircase used by people fleeing the burning towers.

The 9/11 Memorial called Reflecting Absence also houses the largest man-made waterfalls in North America. A competition was held in 2003 to finalise its design.