The National September 11 Memorial Museum

The museum opens almost 13 years after 9/11 to tell the story of the victims and preserve the history of the attacks that killed almost 3,000 people.

. Tridents that once formed part of the exterior structural support of 1 World Trade Center (the North Tower) on display in the museum's atrium. The 9/11 Museum dedication takes place on May 15. John Makely / NBC News

. Situated between the North and South Memorial pools, the glass museum atrium is the entrance to over 100,000 square feet of exhibit space. John Makely / NBC News

. Before the towers collapsed, hundreds of people escaped down the Vescey Street stairs, now known as the Survivor's Stairs. John Makely / NBC News

. Some of the exhibits on display are underneath the footprint of the North Tower. John Makely / NBC News

. Part of the radio and television antenna from the North Tower is on display at the exhibit. John Makely / NBC News

. FDNY Ladder 3 was crushed when the North Tower collapsed. All 11 responding members of Ladder 3 were killed inside the tower. Their last reported position was on the 35th floor before the tower collapsed. John Makely / NBC News

. Fliers of missing people were posted outside of hospitals in the weeks following Sept. 11, 2001. John Makely / NBC News

. A fragment of the fuselage from Flight 11. John Makely / NBC News

. Artifacts on dispay from the attack at the Pentagon. John Makely / NBC News

. The watch and business card of Todd Beamer, who was on Flight 93, which crashed into a field in Pennsylvania. John Makely / NBC News

. A collection of newspaper front pages from around the world the day after the attacks. John Makely / NBC News

. An American flag recovered from the debris of the World Trade Center Twin Towers. John Makely / NBC News

. A deformed piece of "impact steel" is displayed next to the footprint of the South Tower at the National September 11 Memorial Museum. John Makely / NBC News

. One section of exhibits displays artifacts from the extensive recovery and excavation efforts following the attacks. John Makely / NBC News

. A composite of five floors worth of material from one of the Twin Towers that was heat-fused and compacted during their collapse. According to the museum, experts contend that the extreme heat and pressure required to create this artifact would likely render the presence of identifiable human remains impossible. John Makely / NBC News

. The last column removed from Ground Zero is covered with remembrances from friends and family. John Makely / NBC News

. Former New York City Mayor Rudy Giuliani gets a first look at the 9/11 Memorial Museum after a rehearsal for the dedication ceremony. John Makely / NBC News

. The National September 11 Memorial Museum dedication takes place on May 15. John Makely / NBC News