Transcript for Less than 2 years after devastating fire, a first look at Notre Dame’s restoration
Reporter: One of the world's most iconic landmarks. A lesson in resilience. Notre dame. You're saying if you walked past, you wouldn't know anything is wrong, the facade looks as incredible as ever. Reporter: Less than two years after the world watched the notre dame cathedral burn, we're back inside as one of the first networks outside of France to cover its restoration. This is the spot where notre dame suffered most of its damage. You can see the massive hole still in the roof up there. Below, that's where the altar would have been and the gold cross above it. And work continues to try to stabilize the roof here to bring notre dame out of danger still two years later. The evening of April 15, 2019, the world watched as notre dame's structure turned into a towering inferno. The heartbreak from Paris tonight, notre dame cathedral going up in flames. Reporter: The cathedral was so badly damaged that people feared it would collapse. And some of it did. That famous spire crumbling to the ground. My colleague David Muir was given access to the more than 850-year-old structure in the immediate aftermath. This is just remarkable that this was saved. This is it. It survived. They're going to be examining each of the pipes of this great organ to make sure that they haven't been permanently damaged. Just to give you an idea, you can't help but notice the ash and likely lead in here as well that remains, the soot, all over the cathedral. Part of the restoration that lies ahead. Reporter: Now nearly two years and a pandemic later, the teams are still working away to secure the historic cathedral. We head up to the roof where the destruction began. We're about 40 meters up here. The fire started by an electrical fault high up in the vaulted ceiling. And this is what it did and where that famous spire fell. Here, workers dig through remains on the roof. All the old wood, stone, and metal has to be taken out and analyzed before they rebuild. Precious fragments handed off to archaeologists who will see if there's anything they can salvage. Whatever can't be used in the restoration will be preserved to study this ancient treasure. Back on the ground, debris is collected and brought into debts. In this one, restorers have collected the lead-filled beams that fell as notre dame burned. It's a huge operation. We're this part because they're so worried about lead inhalation. You need a specialized mask in order to go in. In another site, shelves lined with stones. These are all the stones that were found on the floor of notre dame that fell during the fire. Each one is meticulously placed in order, to recreate the part of the structure that no longer stands. I asked the archaeologist what answers she hopes to find among the debris. She says, there's so much to discover. Translator: You think a building like this is really well known, but actually, it's such an important building that no one dared touch it. Reporter: The challenge, determining if these stones are structurally sound to be used in the restoration. Next door, a gargantuan task at hand. As you can see, these stones look completely different. That's because they've been cleaned and prepared and placed over here. Prepared to be placed over here to recreate one of the arches from notre dame. Hopefully, one day, to then go back into the building. The one thing that's clear, everyone here is working not just to restore a building, but to rebuild history. France is waiting.
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