Notre-Dame de Paris: the mysteries of reconstruction Guided tour

Those who thought Notre-Dame de Paris was immortal were right. Even the terrible fire on the night of 15 to 16 April 2019 did nothing to change that. When the fire brigade's gigantic water hoses poured onto the burning roof and the religious chants of stunned believers rose from the banks of the Seine, how many of us believed it?

Yet the world's most famous cathedral is about to be reborn even more beautiful, thanks to human genius and courage.

The courage of the firefighters: once again, they put their lives on the line, not just to save human lives, but to protect one of the most majestic witnesses to our history over the centuries. What exactly did they save? The crown of thorns, star of Notre-Dame's treasury, a 13-tonne bell over 200 years old called Emmanuel, and many other works of art with a rich history.

But after a 15-hour battle with the flames, it was time for the investigation. The exact cause of the fire has yet to be determined, but the techniques used in fire investigations will be revealed to you during this guided tour.

The police aren't the only ones conducting investigations at Notre-Dame, as archaeologists have gone from one surprise to another. Two mysterious sarcophagi were unearthed beneath the cathedral's flagstones.

All of this is taking place in the midst of a prodigious study, restoration and reconstruction project that is a testament to France's expertise.

Where were you during the fire?