The French Riviera without art is like a Matisse without the sun. Each needs the other to make sense of itself.So I get why the Instagrammers are outside Le Negresco, a hotel in Nice, clustering around a Niki de Saint Phalle supersize statue of Miles Davis. The jazz musician toots a note of fun at the entrance of the rosy-domed landmark on the Baie des Anges. Le Negresco trumps its competitors thanks to its extraordinary art collection. It covers five centuries of French-art history, teased out in 6,000 pieces from the likes of Renoir, Dalí, and Cocteau. The hotel’s flame-haired owner, the late “Madame” Jeanne Augier, died in January 2019 at age 95. She wanted her hotel to be a museum. In the main Salon Royal are more canapés for the eye. One of two priceless crystal Baccarat chandeliers hangs overhead. Many of Augier’s rich guests offered to buy the place over the years, but she refused. She reportedly even sent Bill Gates on his way. Le Negresco subsequently earned itself historic-monument status and a Michelin star or two for its restaurant. —Catherine Fairweather