They posted selfies and family photos that were taken at Notre Dame days, years or decades before a fire burned through the Gothic churchs roof and brought down the spire on Monday. Some wrote of their disbelief. Others, saying no words adequately expressed their feelings, posted dramatic images of the architectural masterpiece engulfed in flames or the spire falling.
For the French people, the extensive damage felt like a wound to the national identity and served as a reminder of their heritage from the France that was devoutly Christian before secularism became the law of the land.
But millions of international visitors have been to Notre Dame, a must-see during school trips, honeymoons and family vacations. The cathedral has moved people of faith but also inspired non-believers, all finding wonder in the light filtered through stained-glass rose windows and a reward for making it to the top of the stairs.
Even people who havent visited yet said they struggled to come to terms with the loss. The Rev. Philip Hobson, pastor of Mt. Sinai Congregational Church, United Church of Christ in Mt. Sinai, New York, said he felt a connection from movies, putting together puzzles of those famous stained glass windows with his family, and now seeing the pictures and comments of his parishioners.
Our assumptions of what is permanent are challenged. Not sure what to make of all of it, Hobson wrote on Facebook.
Moscow photographer Evgeny Feldman said Notre Dame has been part of an arrival ritual for his trips to the French capital.
It has always been a magical moment for me - to fly into Paris, drop your bags, take the bikes and take a ride by the facade of the cathedral late at night, Feldman wrote on Facebook.
I very much hope that in a few years, in a few decades, I will still be able to take a bike at night (or a hover-board!) and take a ride on the square in front of it and gaze in amazement at the sculpture, towers and stain glass, the 28-year-old wrote.
Famed primatologist Jane Goodall recalled in a posted excerpt from her book Reason for Hope how a visit to Notre Dame during the 1970s marked an epiphany in my thinking about my place on Planet Earth and the meaning of my life.
Goodall said gazing at a rose window in the mostly vacant church, hearing a piece by Bach playing in a distant corner for a wedding, was a suddenly captured moment of eternity and perhaps the closest I have ever come to experiencing ecstasy, the ecstasy of the mystic.
How could I believe it was the chance gyrations of bits of primeval dust that had led up to that moment in time - the cathedral soaring to the sky; the collective inspiration and faith of those who caused it to be built; the advent of Bach himself, she wrote.
Ying Xin, a Chinese dancer with the Martha Graham Dance Company in New York, posted a on Instagram of a dance she improvised in front of Notre Dame last year. Reminiscing about her spontaneous performance, she said she was inspired to dance in front of the monument while walking around Paris on her first night in the city.
It was dark out and the cathedral was stunning all lit up at night. It was the perfect Paris moment, she wrote.
The French president has said he would seek help from the greatest talents in the world to rebuild Notre Dame within five years. Many foreign governments said they were considering contributions to what would be a significant architectural undertaking.
Polish Prime Minister Mateusz Morawiecki recalled how predominantly Catholic Poland rebuilt the capital of Warsaw after German bombs caused vast destruction during World War II.
We will rebuild the Cathedral of Notre-Dame together as Europeans, he vowed.
Rich Matthews, 43, attended a Catholic school in Kansas City as a boy, Notre Dame de Sion. He made a point of seeing the Paris cathedral in 2015, right after coordinated terrorist attacks on Nov. 13 killed 130 people in the city.
His children, ages 6 and 7 at the time, were frightened after the attacks even though they lived in Dallas, Texas. The older one had just attended her first concert - Ariana Grande - and declared she never would go to another after the Paris attackers chose a stadium concert as one of their targets.
My wife and I decided to teach our young children a lesson. We would not be afraid, we would not stop going to things, Matthews said. We had time if we could do our family Thanksgiving Thursday afternoon, we could leave right after it and get back Sunday and be at work and school on Monday. And thats what we did.
He posted a photo of the family in front of Notre Dame with the words: Glad we saw it.
Nataliya Vasilyeva and Kate dePury in Moscow and Sylvia Hui contributed to this report.
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