The good news for Paris’ famed Notre Dame Cathedral is that work to restore sections destroyed by the catastrophic fire in 2019 is back on track. The bad news is that the work could take decades to finish.

After Good Friday services at the neighboring church Saint-Germain l’Auxerrois, Patrick Chauvet, Notre Dame’s rector, told the Associated Press “I can guarantee that there’s work to do!” He then added that the work could take another 15 or 20 years.

Immortalized by Victor Hugo’s The Hunchback of Notre Dame, Notre Dame Cathedral Paris -- or Notre Dame de Paris “Our Lady of Paris” -- is famous around the world. Located on a small island called the Ile de la Cite in the middle of the River Seine, it is one of the first Gothic cathedrals that feature sculptures and stained-glass windows, Notre Dame Cathedral Paris explains.

To put the cathedral’s size and complexity in perspective, its construction began in 1163. However, it took more than 300 years to complete.

Notre Dame Cathedral also is known for its historic neighbors, namely the Louvre, the Eiffel Tower, and Place de la Concord. In fact, the entire area -- known as Paris, Banks of the Seine -- is a UNESCO World Heritage Site.

As you may recall, a fire that is believed to have been caused by an electrical short caused extensive damage to Notre Dame on April 15, 2019. The “ferocious blaze,” an article on theGuardian.com explains, “brought the cathedral’s 96-metre (315-feet) lead and wood spire, a landmark of the Paris skyline, crashing on to the stone roof-vaults.”

The damage could have been considerably worse. Fortunately, authorities in Paris had planned for this type of disaster.

“Following a protocol developed for just such a disaster, firefighters knew which works of art to rescue and in which order,” a Science Mag article explains. “They knew to keep the water pressure low and to avoid spraying stained glass windows so the cold water wouldn’t shatter the hot glass.”

Immediately after the fire, French President Emmanuel Macron announced that reconstruction work on Notre Dame would be completed within five years -- coinciding with when Paris is to host the 2024 Olympics, an ABC News article recounts. That plan, however, was quickly walked back by officials who recognized the scope of work could not be completed so quickly, the article continues.

Compounding the situation, the restoration effort has suffered setbacks. For one thing, a large amount of toxic lead from the cathedral’s roof was deposited on the surrounding area -- and needed to be cleaned up first, the Associated Press article points out. Then, winter storms were followed by France’s COVID-19 lockdown, which further delayed work.

There are still challenges to overcome. As a Le Parisien article notes, the restoration requires carpenters, stonemasons, and roofers as well as master glass makers, cabinet makers, and gilders. However, there currently is a shortage of such craftsmen, who must hold a historical monument qualification, Patrick Liebus, president of the Confederation of Building Craftsmen, says in the article.

Finally, acquiring materials to repair Notre Dame is also a significant obstacle. For instance, the cathedral’s roof contained so many wooden beams it was called la foret -- “the forest.” Experts calculate it will take between 1,000 and 1,500 oak trees -- between 150 and 200 years old -- to rebuild Notre Dame’s spire. After the trees are cut, they must be aged for at least 18 months before they can be cut into beams.