A huge memorial to the people who died has now been finished on the 21st anniversary of the 9/11 terrorist attacks.

At the 9/11 Memorial and Museum at Ground Zero in New York City, the Portrait Wall has tried for a long time to show a picture of each of the 2,997 people who died in the attacks.

Now that the monument is finished, it has pictures of all of the people who died at the World Trade Centers, the Pentagon, and on Flight 93, as well

as the six people who died in the 1993 World Trade Center Bombing.

But putting these pictures together was not an easy job. The project, which began in 2006, wasn't finished until 2014, even though it was first shown to the public in 2014.

In 2016, the New York Times put a story about the exhibit on the front page. This gave some background and information about the seven missing portraits

A federal worker in Washington, DC, read the story and thought that she might be able to help with the search.

The worker told her boss, Department of Homeland Security (DHS) Associate Director Tammy Meckley. Meckley sent researchers to a facility in Lee's

Summit, Missouri, where the agency keeps its records deep underground.

Five of the missing people were Francisco Manuel Chavez, Kerene Gordon, Ching Ping Tung, Wilfredo Mercado, and Michael William Lomax.