Around 19.00h local time yesterday evening, a fire broke out in the Notre Dame in Paris. While the fire has been extinguished, the 800-year-old oak timbers of the roof and part of the stone vault ceiling have been destroyed.

The cathedral’s construction started in 1160 and was largely completed by 1260. The building is considered to be one of the finest examples of French Gothic architecture, and includes innovative use of the rib vault and flying buttress, and enormous rose windows.

The cathedral was largely neglected and desecrated during the French Revolution in the 1790s. Popular interest blossomed again after the publication of Victor Hugo’s novel The Hunchback of Notre-Dame in 1831. In the 19th and 20th century, the stone masonry of the cathedral’s exterior deteriorated due to increased air pollution in Paris, accelerating erosion of decorations and discolouration of the stone.

During the liberation of Paris in 1944, the church was slightly damaged by stray bullets. Some of the medieval glass was damaged and replaced with glass with modern abstract designs. In 1963, the façade of the cathedral was cleaned of centuries of soot and grime, and between 1991 and 2000, a large scale renovation was carried out. Despite this, the cathedral, part of UNESCO’s World Heritage Sites, still showed signs of deterioration, prompting another renovation project, starting in late 2018.

The latter project is probably what caused the fire that started last night. The lead-clad timber roof was engulfed within an hour of flames being seen. Eventually the main spire, built from lead lined oak, collapsed and landed on the wooden roof. The stone vault ceiling has largely remained intact and prevented the timber from causing more damage to the interior. The cathedral’s towers have remained untouched.

The most important relics kept in the church, the crown of thorns, a piece of the cross and a nail from the crucifixion, have been brought to safety, as well as copper statues of the apostles, which were removed last week due to the renovations. The rose windows also miraculously survived the fire.

The roof’s wooden structure was built originally in 1160, and it is estimated that the beams accounted for 13,000 trees, which had been likely growing since the 800s or 900s. The roof was clad with approximately 210 tonnes of lead sheets. The French President Emmanuel Macron vowed to rebuild the cathedral, and already over 300 million euros have been raised to make that happen. While there is enough documentation for a very precise reconstruction, it is unlikely that the craftsmanship will be the same. The stone will be cut using machinery, rather than by hand, and the wood used is not likely to come from entire 300-year-old forests.

The fire is the worst damage the Notre Dame has suffered so far in its history.