New York -- Next week will mark the 12-year anniversary of the September 11th terrorist attacks on America.
More than 3000 people died. Most of the victims were in the Twin Towers of the World Trade Center.
Memorials at the Pentagon and in Pennsylvania, the other sites of attack, are in place.
The 9/11 Museum at the World Trade Center site was supposed to have opened two years ago, but officials say it is still in the works.
The Museum will be built seven stories below the site and contractors say although it has been a complicated build, they promise it will be open by Spring.