Damage from the Notre Dame inferno could've been much worse but for the actions of the firefighters who fought for 14 hours to save what they could.
The blaze tore through the roof of the Paris landmark that's more than 850 years old, toppling the famous spire.
But somehow the fire crews saved most of the historic cathedral, whose unique characteristics made containing the fire an extremely challenging battle.
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With heavy timber construction and soaring open spaces, the structure lacked sophisticated fire-protection systems.
Firehoses looked overmatched as flames raged across the wooden roof, baseball-sized embers soaring into the air as the church burned bright orange for hours.
The 91-metre spire was toppled but authorities say the cathedral's structure - including its landmark rectangular towers - has been saved.
Firefighters formed human chains to rescue precious artefacts that could otherwise have perished in the inferno.
What was saved, what was lost
Crown Of Thorns, Fragment Of The Holy Cross And Nail
The cathedral's most sacred relic, the Crown of Thorns was saved.
Purported to be a relic of the crown placed on the head of Jesus Christ at his crucifixion, it was obtained and brought to Paris by King Louis IX in the 13th Century.
It has been kept under glass since 1896 and only occasionally displayed.
The tunic of St. Louis, a long shirt-like garment from the 13th Century believed to have belonged to King Louis IX, was also rescued, The Washington Post reports.
The fragment of The Holy Cross and Nail may have been destroyed in the blaze.
Supposedly from the cross on which Christ was crucified, the fate of the 24-centimetre piece of wood and 9cm-long nail is not known.
The cathedral's roof was built in the 12th and 13th centuries, using a lattice of giant beams cut from trees in primeval forests.
Experts say France no longer has trees big enough to replace the ancient wooden beams that burned in the Notre Dame fire.
The impressive organ dating to the 1730s and boasting an estimated 8000 pipes did not burn and is intact, but may have been damaged by the heat or water.
"The organ is a very fragile instrument," Bertrand de Feydeau, vice-president of France cultural heritage protection agency the Fondation du Patrimoine, told reporters.
The extent of any damage to the cathedral's bells and their support structure is unclear.
All the original bells were destroyed and replaced after the French Revolution as the cathedral was declared a "Temple of Reason" as part of an anti-clerical movement - except for one.
Called Emmanuel and weighing 13 tonnes, it was joined by nine huge new bells in 2013.
There may be smoke damage to about a dozen large paintings of religious scenes that hung in Notre Dame.
But they appear to have escaped being burned in the blaze.
Called Mays and dating from between 1630 and 1708, the cathedral's greatest paintings will be removed starting on Friday, local time.
Sixteen religious statues got a lucky escape from the fire, The Washington Post reports.
Last week they were removed from the top of Notre Dame for the first time in over a century, to be taken for cleaning.
The removal was part of a restoration of the cathedral's spire, which has been destroyed.