Vauban: The Man Who Tried to Think Like a Cannonball
How a brilliant engineer built France’s fortresses but tried to tear down its injustices
The first time Vauban’s name crossed my path was during research on Louis XIV – but I couldn’t quite conjure up enough interest in a military engineer, however Classical. I wanted art, I wanted culture, not fortresses and stones and war.
And then I saw my first photograph of Neuf-Brisach. Rather than a pile of old walls, I saw a town shaped like a snowflake, sharp and symmetrical, absurdly perfect. My heart nearly stopped. More than four centuries old, and yet it felt like the blueprint of a mind I wanted to get to know. That’s when I started chasing Vauban.
I discovered his mind didn’t work like everyone else’s: Sébastien Le Prestre de Vauban thought like a cannonball. He would walk into a valley and imagine the war from the other side: If he were the enemy, where would he fire? What would he destroy? Then he’d design a fortress to answer those questions.
And forget the intrigues at court – not his style. Vauban was married and had two daughters, though we don’t know much about his personal life. We can find no trace of grand mistresses or courtly scandals, no flashy spending or corruption. The collection of deeply personal letters he left behind were sometimes tender, sometimes despairing, and revealed the occasional detail about him: he loved trees, despised vanity, and kept a garden.
This quiet family man had something special, however: he understood terrain like no one. He would roll up the sleeves of his engineer’s coat and amble out to inspect every site in person, knee-deep in mud. He could walk into a landscape and see its weaknesses. As he toiled on a site and built defensive wonders, he became acutely aware of the lives of the people who did the actual work, and the injustices they suffered. He would draw up plans for fortresses, but also developed a plan for a new society. Even as he built walls for the king, he dreamed of breaking down the injustices they contained. No one thanked him for it – in fact, they punished him. But that came later.
The unlikely rise of a genius covered in mud
Spend any time in France, and you’re bound to come across his name, even if you're not a military history fan or architecturally inclined. He’s the reason so many cities are star-shaped, why so many of his sites (12 in total) are now UNESCO-listed, and why border towns across France still follow the clean lines and solid geometry he built into them, centuries later. You’ll find his presence in well-known sites like Besançon or Neuf-Brisach — but also in quieter towns like Langres, where he reinforced the ancient ramparts overlooking the Marne valley. The stonework still wraps the town like a belt, and the view is no less strategic than in his day.
Vauban was born in 1633 in Burgundy, the son of a minor noble family ruined by war. His father was a poor seigneur who died early and at 17, Sébastien joined the army, not as a dashing officer but as a sapper, digging trenches and laying explosives ankle-deep in clay.
In 1653, during France’s civil war (known as the Fronde), Vauban was fighting for the rebel Prince de Condé. He was eventually captured by royal troops but instead of punishing him for fighting on the losing side, he was rewarded. Cardinal Mazarin (Louis XIV’s powerful chief minister and France’s de facto ruler at the time), and later Louis XIV noticed the young man’s brilliance, and promoted him.
Before he ever built a fortress, Vauban had attacked them. Over the course of his military career, he led the siege of at least 48 cities. It was during one of these – the bloody assault on Valenciennes during the War of Devolution – that he began questioning the sheer cost in human life. He set out to improve siege tactics, coming up with a methodical 12-step process to reduce chaos and casualties.
At his peak, he had fortified over 160 towns and designed a “Pré Carré”, a double line of strongholds around France’s eastern border to keep foreign armies out. It worked, and France was never invaded again on that scale until after his death.
Not everything Vauban touched involved defense. He was involved in one of the more audacious projects of the era: the aqueduct at Maintenon, intended to channel water from the Eure to the fountains of Versailles. It was abandoned mid-construction, both because the War of the League of Augsburg drained the royal coffers and because of technical difficulties – the distance and elevation were too great. While we can’t document his physical presence on site, we do know he was friends with Madame de Maintenon, Louis XIV’s not-so-secret wife.
🧲 Where to walk with Vauban
Here are some of France’s best-preserved Vauban fortifications:
Mont-Louis (Pyrénées-Orientales) – remote, mountain-set military town
Neuf-Brisach (Haut-Rhin) – His geometric masterpiece, an octagonal town built from scratch.
Besançon (Doubs) – His masterpiece citatel, perched on a loop in the river Doubs
Mont-Dauphin (Hautes-Alpes) – A fortified mountain town with sweeping views
Villefranche-de-Conflent (Pyrénées-Orientales) – With a hidden staircase of 734 steps to Fort Liberia
Briançon (Hautes-Alpes) – A fortified city clinging to a ridge above the valley floor.
The king’s engineer turns reformer
While Vauban defended France from outside threats, he became increasingly worried about what was happening within.
He disdained the courtiers of the time, and was more interested in the fate of those well below them in social stature. He wrote thousands of blunt memos and reports, often in frustration, about the injustices they faced. He saw peasants taxed into destitution while nobles and clergy had carefree lives. He saw entire Protestant communities expelled after the revocation of the Edict of Nantes in 1685, and warned that the kingdom was hemorraging talent and labor.
In 1707, a year before his death, he completed an unthinkable manuscript: La Dîme Royale. It proposed a flat income tax applied to everyone and called for the redistribution of wealth and an end to religious persecution.
Louis XIV reacted with icy but predictable fury. The manuscript was quietly banned and it vanished from circulation. At court, people avoided Vauban. The man who was once the king’s favorite engineer was more or less dismissed from court. He retreated to his estate in Bazoches and died that same year, at 74.
Why so many French cities look like stars
Vauban stopped building fortresses whose medieval walls would crumble at the first cannonball and replaced them with star-shaped bastions surrounded by a series of defences that would slow attackers and increase firepower – like Neuf-Brisach. From the air, they look like snowflakes, pointy and symmetrical and strangely attractive.
These were more defensive puzzles than walls, with their raised guardhouses and moats. The shape will be familiar to you if you’ve ever been to Besançon, Mont-Dauphin or Villefranche-de-Conflent, with their geometry and a clear obsession with detail. But Neuf-Brisach was his crown jewel, the most advanced of the nine new towns he created from scratch, its walls designed to eliminate blind spots and maximize defense. It had two layers of protection: an outer star-shaped wall and an inner octagonal one. If attackers broke through the first, defenders could fall back to the second and keep fighting.
At Villefranche-de-Conflent, rather than tear down the old walls, Vauban built on them. He added a second covered walkway above the existing one, doubling the ramparts and creating two rounds of protection. Just above town looms Fort Libéria, accessible via a hidden staircase of 734 steps, and nearby, the Cova Bastera, a natural cave he turned into a fortified outpost.
In Camaret-sur-Mer, a fortress even earned a town a tax break. The Nine Years' War that pitted a massive European alliance against Louis XIV was raging. On 18 June 1694, Anglo-Dutch forces seeking to seize the strategic harbor of Brest attacked the coastal defense tower known as the Tour Vauban. But thanks to the newly completed lower battery, soldiers and townspeople pushed them back. The king rewarded Camaret with a full exemption from taxes, a royal favor that lasted until the Revolution.
One of his cities still trains soldiers today. Mont-Louis, perched 1,600 meters up in the Pyrenees and entirely designed by Vauban in 1679, now houses France’s National Commando Training Center. His geometry has outlived the wars it was meant to fight. And while Vauban’s biographers often paint him as a machine of efficiency, in fact he was a man who deeply loved his country and who dreamed of justice as much as victory.
On the blog:
14 of the Best-Preserved Walled Cities in France (many of them courtesy of Vauban)
Also of interest: Vauban Fortifications protected by UNESCO
Enjoying your read? Please invite a friend to subscribe!
Planning a trip to France? Visit my blog at OffbeatFrance.com and explore France’s lesser known corners, without skipping the places you’ve always dreamed of seeing, of course. Practical, curious, and a little unexpected.