Millions watched as the famous spire atop the cathedral came crashing down in 2019.
Nat Geo was given rare access as more than 2,000 people worked to resurrect the beloved landmark.
Tomas van Houtryve was one of the few allowed to document the restoration.
"Because of the lead contamination on the site, they sort of set up these barriers and locker rooms before you could get inside," he explained. "You have to take off your street clothes and put on a hazmat suit. So it was kind of a universe all of its own, this hive of activity."
After five years of nonstop work, Notre Dame is set to reopen on Dec. 7, a stunning feat.
In that short time, more than 2,000 statues and decorative features were restored or recreated, including the 52 famous chimera statues.
To repair the roof, 43,000 square feet of lead was used. And the spire now stands tall again with one unique change.
"Everything else has been rebuilt, identically as it was before the fire," van Houtryve said. "Except for the rooster at the very top. And the main thing they changed is the wings sort of turn into flames as they go up. And so it looks a little bit more like the mythical phoenix rising from the ashes."
Take a look at the full feature at natgeo.com.
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