It took a little more than an appeal to the gods for Valéry Grégo to transform a convent in the heart of Nice into the stylish Hôtel du Couvent. Now complete, with 88 rooms, three restaurants, and Roman-inspired baths, the decade-long project cost $100 million and included a battle over a building permit, along with a lot of soul-searching.

But Grégo, the French founder of the London-based Perseus group, hasn’t become one of Europe’s most influential hoteliers by avoiding challenges. A Sciences Po graduate with degrees in history and philosophy, he made his name by turning tired, three-star ski hotels into polished, thoughtfully designed resorts.

It all began in 2011, when he acquired Le Val Thorens, and he soon added the nearby Fitz Roy, and Hotel des 3 Vallées in Courchevel. Next came L’Alpaga in Megève.

Top, rooms are sparsely decorated, if not exactly ascetic; above, some rooms have far-off views of the sea.

Perseus’s first seaside property, Les Roches Rouges in the Riviera village of Saint-Raphaël, reopened in 2017. Les Roches Rouges is now owned by the Beaumier group, but when I visited it, several years ago, it was precisely what I wanted from a hotel on the Mediterranean, from the seawater swimming pool to the novels chosen for my room.

At Hôtel du Couvent, Grégo and his team have managed to locate the sensuality within the serenity. Designed by Festen Architecture, the Paris-based design team comprising Hugo Sauzay and Charlotte de Tonnac, the hotel is beautifully simple—terra-cotta-tiled floors, soft textiles in the faded colors of vintage Nice, and unobtrusive furnishings. Oil paintings hang on the limewashed walls, tables are strewn with books, and the only conventional luxuries are the striking stone vanities and marble-lined showers.

The rooms owe their charm and elegance to Festen Architecture, the Paris-based design team comprising Hugo Sauzay and Charlotte de Tonnac.

The convent contains 38 rooms, and the remaining 50 occupy a former 18th-century apartment building, an annex at the entrance to the property, and a sparkling new wing. The visual harmony was difficult to achieve, but Grégo and the team from Festen prioritized the flow from room to room.

“Because it’s a protected historical monument, there was very little we could do in terms of modifying its essential design,” says Grégo. “We created the hotel with the knowledge that it will be just a passage in its history. We hope it lasts a very long time, but that’s unknowable.”

Top, the convent’s ecclesiastical architecture remains intact; above, a slim swimming pool.

For now, at least, Hôtel du Couvent is a delight. Birdsong and the fragrance of orange blossoms emanating from the courtyard telegraph a sense of calm, and the staff’s relaxed hospitality is a welcome relief from the tiresome niceties of many of Nice’s grandes dames. The hotel’s courtyard will eventually host a market that will be open to the public. “We want people who live in the neighborhood to feel welcome here,” says Grégo.

Chef Thomas Vetele oversees the restaurants, which include a bistro, a café near the pool, and a gastronomic affair specializing in the cuisine of southern France, sometimes with a twist. “A sushi restaurant in a place like the convent would be obscene,” says Grégo.

Top, even the food deserves reverence; above, a library that’s anything but stuffy.

An apothecary dispensing herbal teas made from plants grown in the convent’s gardens also sells potions and unguents that make excellent gifts. The baths were inspired by those found in nearby Cimiez, the hillside district above the half-moon-shaped heart of Nice that is demarcated by train tracks and the Mediterranean.

There’s plenty to see and do just outside its walls. Les Petits Farcis, a cooking school from Canadian chef Rosa Jackson, is just a few steps away and offers classes in Niçoise cooking. And don’t miss meals at Onice, where a young Italo-Argentinean couple who previously worked at Mirazur just won their first Michelin star, and Chez Davia, which is to Nice what Chez L’Ami Louis is to Paris but with much better food.

Le Negresco, on the Promenade des Anglais, has been a stalwart of Nice’s hotel scene since it opened, in 1913.

It wasn’t all that long ago that the Belle Époque–vintage Negresco hotel proclaimed Nice’s opulence and ostentation to the world. But now the city’s attitude is softening, and the understated, thoughtful beauty of Hôtel du Couvent feels just right.

Rates at Hôtel du Couvent begin at $600 per night

Alexander Lobrano is a Writer at Large at AIR MAIL. His latest book is the gastronomic coming-of-age story My Place at the Table: A Recipe for a Delicious Life in Paris