Smoke billowed from the heart of Paris last month, as the city’s firefighters sought to control the inferno that engulfed Notre Dame Cathedral. Time seemed to stop as we watched the flames topple the spire, ravage the roof, and threaten the towers.

Crowds of emotional bystanders, some with streaming tears, gathered on the quays in a hushed, horrified silence that occasionally was broken by collective song and prayer. "Ave Maria," they sang. "We salute you, Maria."

Flames and smoke rise from the blaze at Notre Dame on April 15 that destroyed its spire and its roof but spared its twin medieval bell towers.
Thierry Mallet / AP
Flames and smoke rise from the blaze at Notre Dame on April 15 that destroyed its spire and its roof but spared its twin medieval bell towers.

Miraculously — and we needed a miracle during the Holy Week catastrophe — the 400 Parisian pompiers were able to extinguish the fire in time to save much of building and its treasures. They worked late into the night, pumping water directly from the Seine.

A gentle drizzle tumbled from gray skies the next morning as I walked my youngest daughter to school in the city where I’ve lived for more than a decade, and I found myself crying with her kindergarten teacher.

Notre Dame’s importance to the French — indeed, the world — cannot be overstated. Presiding over the Ile de la Cité, the island in the Seine that was the site of Medieval Paris, the cathedral is an enduring and beloved symbol to Christians everywhere; people of any faith or none appreciate its beauty and artistry. A medallion embedded in the square outside indicates Point Zero, the starting point for all roads leading to other cities.

The Basilica of St. Denis was the model for Notre Dame and the burial ground for the French monarchy.
Gilles Messian
The Basilica of St. Denis was the model for Notre Dame and the burial ground for the French monarchy.

Bishop Maurice de Sully laid the cathedral’s first stone in 1163, and the colossal construction was not completed for nearly two centuries. Some 52 acres of trees were cut down in the 12th century to create the intricate timber charpente, or framing, often equated to a “forest” with each beam coming from a single tree. The flying buttresses served an innovative architectural function, providing exterior support to the walls of the nave, allowing for abundant stained glass, including the majestic rose windows that date from the 12th and 13th centuries and survived the fire.

Notre Dame is also the sacred home of Catholic relics including Christ’s Crown of Thorns and the tunic worn by St. Louis. These relics were saved, along with paintings that will be restored in the Louvre Museum.

Badly damaged during the Revolution, Notre Dame played a starring role in Victor Hugo’s famous 1831 novel, The Hunchback of Notre-Dame. The book’s runaway success drew attention to the plight of Quasimodo’s hangout, and a petition resulted in the triumphant restoration by architect Eugène Viollet-le-Duc. Between 1845 and 1864, Viollet-le-Duc oversaw an extensive renovation, adding new flourishes, including the now-fallen spire and the fantastical gargoyles on the rooftop.

 St.-Etienne-du-Mont sits in the shadow of the Pantheon in the Latin Quarter.
David Iliff
St.-Etienne-du-Mont sits in the shadow of the Pantheon in the Latin Quarter.

Notre Dame is France’s most-visited monument, welcoming more than 13 million people a year. It’s particularly packed at Christmas, when an enormous village creche scene is populated with Provençal figurines. Visitors flocked to hear the concerts played on the Master Organ, one of the world’s largest. Lines to climb the towers (422 steps) used to stretch around the block.

Just a few weeks ago, I paid a visit to test out a new app, called JeFile, which conveniently expedited the process. From the top, the Parisian panoramas take your breath away — an experience made sublime by the tolling of the bells.

The cathedral will be closed for years — even decades — for rebuilding. Tourists surely will continue to stream to this City of Lights and stop in reverence at Notre Dame. Even so, there are other exquisite churches, including one that has a direct connection to Notre Dame: the Basilica of St. Denis.

St.-Etienne-du-Mont sits in the shadow of the Pantheon in the Latin Quarter atop a hill honoring St. Genevieve, Paris’ patron saint, whose prayers are said to have stopped the invasion by Attila the Hun in 451 AD. A graceful study of flamboyant gothic architecture, the church appeared in Woody Allen’s film Midnight in Paris; Owen Wilson’s character is picked up from the stone steps in a vintage car.

 St.-Germain-des-Prés.
Guilhem Vellut
St.-Germain-des-Prés.

St.-Germain-des-Pres is considered the oldest church in Paris. It is a Romanesque monument overlooking the cafés that defined the neighborhood as a lively gathering place for the 20th-century literati.

Nearby, St. Sulpice, with marvelous frescoes by Eugene Delacroix, was popularized in Dan Brown’s The Da Vinci Code.

St. Sulpice.
Guilhem Vellut
St. Sulpice.

On the Ile de la Cité, not far from Notre Dame, Sainte-Chapelle was originally built in the 13th century to house the holy relics, including the Crown of Thorns, purchased by Louis IX. With 15 stained-glass windows, the light-filled chapel resembles a reliquary, a purpose-built jewel box for relics.

 St.-Eustache.
Pavel Krok
St.-Eustache.

On the Right Bank, 16th-century St.-Eustache represents a mélange of architectural styles and hosts wonderful concerts.

High above the city, the Basilica of Sacré-Coeur is a vision in white atop Montmartre. Built only somewhat recently — the 19th century — Sacré-Coeur offers sweeping views over the city.

The Basilica of Sacré-Coeur.
Guilhem Vellut
The Basilica of Sacré-Coeur.

But perhaps the most sacred of all is the place where gothic architecture was born. The Basilica of St. Denis was the model for Notre Dame and the burial ground for the French monarchy. Only 130,000 yearly visitors venture to the hardscrabble northern suburb of St. Denis, which developed a reputation as a problematic banlieue after the 2005 riots but is shaking it off with a flurry of street art projects, craft breweries, and an urban farm.

The legend goes that St. Denis, the first Bishop of Paris, was martyred in 250 AD in present-day Montmartre. From there, he walked four miles, carrying his decapitated head in his hands, until he collapsed. His tomb at that site became a place of pilgrimage, with the saint’s bones carefully preserved in a box to awe the swarming crowds. In the eighth century, Charlemagne consecrated an abbey, and in the 12th century, Abbot Suger turned it into a masterpiece.

"Suger was a genius, pioneering the first example of gothic architecture," guide Charlotte Pecheux explained my recent visit. "His idea? God is equivalent to light, so more light was needed to enter the building."

What had been a dark, Romanesque structure morphed into an architectural laboratory with cross vaults negating the need for wall supports. These were replaced by large, stained-glass windows, and colors danced on the walls. The basilica’s inauguration drew a large crowd, including the French king — attendees were so dazzled they resolved to copy it in their own dioceses. Work on Notre Dame started 20 years later.

The churches are free unless otherwise noted. Hours vary seasonally and around holidays, so check the websites, including for guided tours.

Basilica of St. Denis: 1 Rue de la Légion d’Honneur, 93200 Saint-Denis. Tickets: About $10. Information: saint-denis-basilique.fr/en

Sainte-Chapelle: 8 Boulevard du Palais, 75001 Paris. Tickets: About $11. Information: sainte-chapelle.fr/en

Church of St.-Étienne-du-Mont: Place Sainte-Geneviève, 75005 Paris. Information: saintetiennedumont.fr/en

Church of St.-Germain des Prés: Place St.-Germain des Prés, 75006 Paris. Information: eglise-saintgermaindespres.fr (in French)

Church of St. Sulpice: 2 Rue Palatine, 75006 Paris. Information: pss75.fr/saint-sulpice-paris

Church of St.-Eustache: 146 Rue Rambuteau, 75001 Paris. Information: saint-eustache.org/en

Basilica of Sacré-Coeur: 35 Rue du Chevalier de la Barre, 75018 Paris. Tickets: basilica, free; dome (300 steps), about $7. Information: sacre-coeur-montmartre.com/english