Construction on a memorial and museum at the site of the World Trade Center is under way in New York, as the fifth anniversary of the September 11, 2001 terrorist attacks approaches.

World Trade Center Memorial and Museum (architectural drawing)

The World Trade Center Memorial and Museum is being built on three hectares of the original 6.5 hectare Ground Zero site. The centerpiece will be a memorial called Reflecting Absence. In the place where the massive Twin Towers once stood, water will cascade down the sides of two voids in the ground, with reflecting pools 8 meters below ground. The names of the victims will be inscribed around the pools.

Alice Greenwald, the director of the Memorial and Museum, says the design is meant to represent the loss of life and the loss of buildings.

"We expect that the visual dialog will be a kind of creative tension between an awareness of the enormity of scale architecturally of this space, recognition of the physical absence of the buildings that stood here and the fact that this place memorializes individual human lives," said Alice Greenwald.

Surrounding these voids will be the Memorial Plaza, filled with oak trees to provide a serene and contemplative space for visitors.

The Memorial Museum features objects and artifacts retrieved from Ground Zero. The majority of the items are coming from a variety of archival, cultural and historical institutions around New York state. Greenwald these institutions acted cooperatively to save items from the site after the attacks.

"They said 'we must document this material before it gets taken away, we must collect the evidence of this event," she said. "This is our responsibility as custodians of history and of material culture' and they worked together to do this. They also made a commitment, mutually, that has reaffirmed again and again that when there would be a museum, an interpretative center, dedicated to telling the story of the site, every one of these institutions has pledged to make their materials available to us."

Greenwald says the museum will focus on the events of 9/11 and it's impact on New Yorkers and the world.

"On 9/11, for Americans as well as people in nations around the world, a sense of America's invulnerability was shattered by an event's whose order of magnitude challenged our collective imagination," explained Alice Greenwald. "As a museum of memory, at a site of atrocity, in the midst of a vital urban center of commerce and culture, how do you address this? We have a few guiding assumptions. The specificity of what happened here must be our primary story, not just the horrific events of the day, but the response of the community, the uniformed rescue personnel, New Yorkers, Americans from every state, the world community. And ultimately, the story must be about the people affected by this event."

The memorial and museum will also commemorate the victims of the February 26, 1993, attack on the World Trade Center.

The non-profit World Trade Center Memorial Foundation is overseeing fundraising efforts for the Museum and Memorial. But the project has been delayed several times by disputes over design, budgets and the content of the museum.

Greenwald says the foundation hopes the museum will not only make people remember the attacks, but also think about the future and start a dialogue that continues after their museum experience.

"Ultimately, by focusing on the human story, it is our hope that this museum will become a moral platform attesting to the indefensibility of terrorism - to the absolute unacceptability of indiscriminate mass murder as a response to grievance," she said.

World Trade Center Memorial and Museum construction

Construction on the museum began August 17. It is slated for a partial opening in 2009. Other components of the museum are scheduled to open at a later date because of ongoing building around the site.

Meanwhile, the WTC Memorial Foundation is sponsoring photography exhibits around Ground Zero to help visitors to the site.