The Carlton is the undisputed star of the French Riviera. Massive, white and marble, it sits on the famous La Croisette seafront in Cannes. And in a town where everyone is finely tanned, rail-thin, and wears jewels to breakfast, the Carlton’s clientele is the most dazzling. It has the best parties, the most beautiful people, and the most stars lunching — due, partly, to its role as the unofficial center of the annual film festival. But even outside of those two weeks in May, its atmosphere is unsurpassed. Grace Kelly and Cary Grant chased each other here in To Catch a Thief, and off-camera, Kelly met her future husband Prince Rainer. Today you might see another princess, for in all the Côte d’Azur, it’s the only hotel that royalty continues to patronize. But the Carlton is also tough. When Italian fascists mined the hotel in 1944, they built an underground room to hide their wine. And though its staff is famously secretive — they have to be, with the number of high profile guests and scandalous carryings-on — the architecture itself is shockingly indiscreet. It's been said that the gorgeous domes on either side were inspired by the breasts of famous courtesan La Belle Otero. Though the regulars have ranged from Sophia Loren to the Coen brothers, the Carlton is still associated with the late Princess Grace. You can feel her untouchable blonde presence in the bedrooms. The décor hails straight from the sets of one of her 1950s movies; it's pale, Riviera, Belle Époque and fit for a swan. Of course, whatever you do behind its elegant doors is your (and the staff’s) secret alone. By the way, don't think that you can shock the staff with your requests, or make them sweat. They’ve handled everything from a princess with 120 suitcases (she reserved three rooms for her clothes) to a gentleman who ordered 100 kilometers of barbed wire from the concierge (he wanted to build a fence for his estate). Naturally, they’ve witnessed a lot more, but they aren’t telling. For the last five decades, the best people-watching in the evenings is to be had at the bar Le Petit Carlton (not at the Bar Des Celebrities) where you will find the glitterati sealing their business deals and their liaisons. Thankfully, the bartender also pours a generous cocktail — just in case you want to chat up Robert De Niro, pitch a screenplay to Wim Wenders, or simply forget about the amount of money you’ve spent — which at Cannes, with its shopping, lunches, and casinos, is incredibly easy to do.