AUSTIN, Texas — The world watched in horror Monday, as Paris' Notre Dame Cathedral burned.

• Local experts weigh-in on Notre Dame Fire
• Say this is "completely devastating"
• Officials still don't know the full extent of the damage

"A fire like that is completely devastating,” Amy Fulkerson, Chief Curator at the Witte Museum said. “You’re looking at not only religious and culture treasures that have been destroyed, but you're also looking at tremendous structural damage. So this is a site that may never look the same again."

The church's roof and iconic spire collapsed amid the flames.

"This is a pivotal building for our study of gothic architecture,” Joan Holladay, a professor of art history at University of Texas at Austin said. “To lose it and to lose what we call the building archaeology, the way the stones are put together, the way the flying buttresses are integrated into the walls, it would be a major loss."

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Though authorities were able to safely remove much of the church's precious art, the damage to the organs, sculptures, and other treasures are still unknown.

"The choir screen inside dates to the beginning of the 14th Century. It's well documented, we know a lot about it... it would be devastating if we were to lose that,” Holladay said.

Officials say they were able to keep the fire from the cathedral's two rectangular towers, preserving one of its main facades and some of its most historical sculptures.

"There's also really famous and wonderful sculpture on the outside,” Holladay said. “So when one stands in front of the cathedral, on the right hand portal, on the right door, is sculpture from the 1160s. That was installed there in the decade of the 1220s and into the 30s. On the left hand portal is sculpture from the 1220s, and in the middle portal is the Last Judgment Scene, most of which dates to the 1230s we typically think."

Officials still don't know the full extent of the damage.

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"What burns most readily in a cathedral are the wooden beams that support the roof. So when you stand in the cathedral and look up, you're looking up at stone vaults. Above those is a wooden framework that supports what is typically a lead roof... but lead melts of course if those wood beams underneath it catch fire, and then when the whole thing starts to collapse. Big pieces of things are falling through the vaults and destroying what's inside the building as well,” Holladay said. “It may be a decade or more before the building can be reopened again depending on what they discover tomorrow morning.”

French President Emanuel Macron has already announced the city will rebuild the cathedral, but for now, the world mourns for Our Lady of Paris.