PARIS — Since my family and I arrived for a visit Sunday morning, we’d spent a lot of time outside Notre Dame without actually entering, deterred by long lines. Instead, we’d been holding out our arms for pigeons in the hope they’d land on them and taking video of the Palm Sunday procession that came through the square, with bishops and a cardinal in his bright red robes waving palm fronds. The bells had rung crazily, joyfully. Years ago, I had sat by myself on a bench, brought nearly to tears by gratefulness for this structure that had watched Paris through centuries of life.

On Monday around 6 p.m., our eldest said she still saw many people in front of Notre Dame. We decided we would go back to our Airbnb just a few blocks from the church to make dinner, then check the website to see how late it was open. Just as we sat down to eat, my daughter looked out the window and asked, “What is that from?”

Dark smoke billowed past our fourth-story window. We were in a medieval apartment building, at the top of a thin and steep staircase. On Sunday night, I had laid awake in bed thinking about what we would do if there was a fire. I assumed one of the many ground-floor restaurants on our street had had a kitchen fire. So we put on our shoes, grabbed our passports and headed downstairs.

We followed the crowd on the street, standing beside the Saint-Julien-Le- Pauvre church, just across the river Seine from Notre Dame, with hundreds of others to watch what was initially just a bright fire on the roof behind the two main towers of the cathedral. Our view was from the Left Bank, at four o’clock if Notre Dame was 12.

The fire quickly spread; scaffolding became visible. The crowd was strangely quiet. Only a few people were taking photos or recording video; it seemed more like a moment to watch in concerned silence.

Fire was the scourge of medieval cathedrals. They rebuilt from the ashes.

Periodically, people would come to the side yard of Saint Julien and try the locked gate; a guard pointed to where they should go. My husband helped a man with a bike push it over, but when the man then tried to climb over himself, the guard yelled at him. I assumed everyone had safely gotten out from such a vulnerable proximity to the fire, until 20 minutes later, when someone official unlocked the gate and a flood of traumatized-looking people exited the garden onto the street.

Police yelled to push us back, and we retreated, but we could still see the flames on the roof. Black smoke emanated from the rear rose window. We heard several loud explosions. Mental comparisons to the twin towers of Sept. 11 were unavoidable, and I began to fear that the two main bell towers might fall. Although there was a river between them and us, it felt like debris might rain down on our heads.

Our youngest daughter was very anxious, hugging her stuffed mouse. A month ago, seeing her sister get a liquid nitrogen freeze from the dermatologist, she had nearly fainted. I feared she would do so now. We left the scene, with mixed feelings: I wanted to keep our vigil, but it was cruel to force her to stay when she was that upset.

Our apartment was so close to the fire on rue de Saint Jacques that we didn’t feel comfortable going upstairs. We waited in the ground floor courtyard until smoke significantly diminished. We finally ate the dinner still sitting on the table.

Afterward, feeling much calmer, we felt that we could return to the site to see what was happening. My youngest created an emergency pack: a flashlight, sugar cubes for eating and tissue in case we wanted to cry. At the end of our block, the crowds were far too thick to penetrate further. Feeling the buzz of Parisians stunned by such a loss, we were unwilling to retreat to our solely American company.

We sought out crepes. As the crepe maker stood there over his circular hot pad, I asked him if he was worried about the fire. “I don't understand,” he said. For a moment, I thought he somehow had not heard about the nearby fire. But with a Gallic shrug, he explained that the fire was behind him. It would not spread. He would simply keep making crepes.

It occurred to me that this is how Parisians confront trouble: They’ve been through worse. They’ve been occupied, been besieged. Earlier Monday, I looked at a plaque on a preschool that memorialized the Jewish students rounded up and taken to concentration camps. What’s a fire in a building that has comforted worshipers and provided sanctuary for hundreds of years? It has more than done its job.

Paris has changed so much in the three decades I’ve been coming here. I saw the Impressionist masters housed in the Jeu de Paume before the Musée d’Orsay opened. The Montmartre hotel where my husband and I stayed on our first trip here together is now gone. Back then, we visited the Orfila museum, with life-size wax women giving birth; those collections have since been relocated to Montpellier. On Monday, we were at the Conciergerie, the prison where Marie Antoinette was held for 76 days before being guillotined. I told our children we would see mannequins in the cells, lying on straw to show how desperate conditions were for prisoners who could not afford to bribe their jailers. Yet the cells were empty. Worse, I couldn’t find the chamber where Marie Antoinette faced her last days. To my surprise, the guides told me that I was in her chamber, which now houses general exhibits and lacks even a single plaque to denote that this had been the room in which she’d heard the roar of the crowd as her husband was executed. I started mentally cataloguing all the things I’ve loved and watched disappear in Paris.

Paris will keep losing things, and I will mourn them. Notre Dame’s beauty, history and solace seems tangible, and I will regret that our children did not get to see that interior before it is rebuilt. But the spirit of Paris is one of Gallic shrugging. The crepe maker was right. Paris will always endure.