Transcript for Rebuilding Paris’ Notre Dame Cathedral
The world certainly watched in horror nearly two years ago as the famed notre Don nearly 1000. Years old burned despite the pandemic the restoration work has continued and are James long and has an exclusive look at the resurrection. Of this famous cathedral. Nearly two years ago as the world watched in horror as an emblem of French national pride and identity notre them. And as night fell on April 15 2019. The night men reached its climax. That famous by a crumbling to the ancient cathedral. The structure fragile and despite a pandemic that shut down life as we know it. The work on rehabilitating this extraordinary place continued. Today this historic treasure is slowly pulling through. And we went in Sewell first term. To get pocono. Here's Saturday into what parts they wouldn't that everything wrong from the facade Phillips is incredible as. Inside an 80000 year old cathedral it's a difference to re. We had up to the roof. But the destruction began. Or about fourteen meters out there. The fire was started off pay applying electrical full high up in the full succeeding and this is Steve and went down famous client felt. This is the most obvious damaged and also down the Canadian norm let's hold the remains. In the roof of the building take a look you can see. That show dog ends. All of what was once the boat volts that kept this part of the roof in place. And it was that is 200 tons of lead to melting down on top of the roof say that led that once lined history. That cools this part of the roof. To collapse. There are now and it will be 250 to 200 people working on off and on any one time slowed down of course by the pandemic. Here workers dig through remains on the roof all the old wood stone and metal has to be taken out and analyzed before they refilled. Precious fragments handed over to archaeologists. We'll see if there's anything they can salvage whatever it can't be used in the restoration will be preserved to study the nearly 1000 year old structure. Mark on the ground debris is connected and pointed to tense in this one illustrators have connected the lead filled beams that fell as notre down. It's a huge operation smashing and even on out in today's pop the confess I worried about led inhalation do you specialize mosque. In order to go then in another site shelves lined with students so these are all the Stein's. The were found on the floor not turned on the fell during a fire this us. Each one is meticulously placed in order to re create the pump to the structure that no longer stands. Playoffs the archaeologist what on says she hopes to find among the debris. She says there's much to discover. And indeed his come 7 o'clock senate. Pick and you think a building like this is really well known but actually it's such an important building that no one dared touch it. The challenged determining if these stones are structurally sound to use in the restoration. Nick stool a gargantuan task at hand. Did you see these studies looked completely different us because they've been clean debris pads and place I've hair for Patrick faced eight to re create one of the offices from not Saddam. Hopefully one day thing go back into the building. They using a model from American art historian Andrew talent. He was the last person to property not to vaulted ceilings of this part of notre down in 2010. Because the originals a lost. His plans are the only ones that teens he can go buy it. Devastated and I kept the ceremony chisel is going to cost and how long would it take. The deputy corporations that notion down walls and a little shy. Her upper. But it's clear this is an unprecedented project and the level of expertise and she and number of skilled crafts people requires this. Doctorate there you substantive by that point saluted. We gathered hundreds of stones from the first few days thanks to a scientific community who mobilized today right after the fire. Scientists architects archaeologists. Do they all volunteers to rehabilitate the structure of. The one thing that's clear everyone here is working not just a restore building but to rebuild history. And France is waiting. James omen in Paris for ABC news life. Quite a task they are thanks to James that old sidewalk.
This transcript has been automatically generated and may not be 100% accurate.