But relatives of the victims have expressed dissatisfaction with the building progress.
Jim Riches, Father of 9-11 Victims, said, "I think it's a national disgrace, I mean, it's eight years later. I mean everybody is saying we put the last column in there, and they brought it back. Eight years later and that's all we have done. "
The 9-11 memorial is scheduled to open to the public 2011, on the tenth anniversary of the attacks.
The underground museum is scheduled to open a year later in 2012.
The names of nearly 3-thousands victims will be around two waterfall-filled pools.
