We know that everyone—visitors, transplants, locals—has an opinion on the Upper East Side. Known as a home to the wealthy and to some of New York's most beloved cultural institutions and attractions, the Upper East side has been depicted in films, television series and books as a bastion of the gilded "old New York." But nowhere on the Upper East Side is that more apparent and as concentrated as on Madison Avenue, where the likes of the Rockefellers, Vanderbilts and Astors began moving to in the 1890s. The strip between East 57th and East 86th streets is known for world-class fashion, contemporary art, fine dining and everything in between. What makes it different from other hubs of art, culture and luxury is that Madison Avenue still feels (and actually is) very residential, despite its stores and amenities. Wander the avenue on a sunny morning and you'll spy ladies in shades and tailored suits walking manicured poodles, nannies pushing SUV baby carriages, consulate officials chatting over coffee and croissants, and huddles of plaid uniformed kids jostling and texting their way to private schools. So make your way to Madison Avenue and live out your most luxurious day on the Upper East Side.Shop (or browse) with style at flagship boutiquesWhen it comes to shopping, Madison Avenue is all about haute couture. Jewel-box boutiques for , and alongside over 150 other shops line the avenue. The massive flagship even comes with a cocktail bar, VIP lounge, rooftop garden and in-house atelier. Even with all these shopping options, the neighborhood remains residential and relatively quiet—especially compared with shopping neighborhoods like Soho or Midtown. Before the influx of luxury boutiques, wealthy New Yorkers traditionally traveled to Europe to see their ateliers. By the 1980s, the major European fashion houses realized they could service their clientele more conveniently by opening branches here (a trend that started in the late 1960s with Yves Saint Laurent's Rive Gauche boutique).While most shoppers in Soho and Fifth Avenue tend to be visitors, Madison Avenue is still primarily frequented by locals, with Succession-inspired "stealth wealth" fashion as vogueish as checkered Chanel suits. Today, NYC-based designers on the strip include , , and , whose flagship Bridal House is a magnet for brides to be. 's massive flagship spans both sides of the avenue, incorporating the elegant French Renaissance–style Rhinelander Mansion and chic where you'll be mixing with luxury shoppers and socialites over cappuccino and cookies.Check out niche brandsMadison Avenue has had an influx of hip new designers and retailers in the last few years. Peruse the latest trends at , , , and Stacey Bendet's , or try the premium denim and knitwear at . Meanwhile, is the poshest secondhand clothing store you'll ever visit.Admire the jewels at De Beers and Irene NeuwirthWhile most visitors crowd into Midtown's Diamond District or Tiffany & Co. for posh jewelry, Upper East Side glitterati go straight to the source at . The customer service is top-notch, as are the products, and you'll rarely have to wait long to see an expert. For something out of the ordinary, visit Los Angeles–based jewelry designer , whose whimsical, brightly colored creations are popular with Hollywood stars like Tracee Ellis Ross, Julianne Moore, Ruth Negga and Gwyneth Paltrow.Marvel at contemporary art in NYC's top galleriesThe same wealthy families that enticed fashion houses to set up shop here were also avid collectors of fine art. Ever since trailblazing dealer opened his gallery here in 1957, Madison Avenue has been a hub for art lovers, with over 100 galleries at last count. Unlike the large but minimalist warehouses in Chelsea, the galleries here are more intimate, set inside late 19th century townhouses that exude Gilded Age elegance. Castelli's gallery is still here, with the equally celebrated , and Swiss outfit , all specializing in modern and contemporary art.Hit the spaNeed to unwind for an hour or two? Madison Avenue's exclusive day spas provide relief, with pools, saunas, steam baths and multipage menus of beauty treatments. The offers facials, luxurious body treatments and massages, as well as spotless steam and shower facilities, while the relatively new on the other side of the avenue has bespoke, physician-supervised skin care, massages and facial acupuncture.Live out your Sex and the City fantasyMadison Avenue and the Upper East Side have added glamour to movies like Breakfast at Tiffany's and TV shows like Gossip Girl, Sex & the City and, most recently, And Just Like That… (Carrie and Charlotte are Upper East Siders in the series). Ms. Bradshaw famously loves to shop for shoes at Madison Avenue boutiques , and . You can mingle with well-heeled locals at cafés and restaurants that featured in both SATC series and admire the big Buddha at .Sample a French sweet treatThe students at Gossip Girl's fictional Constance Billard School for Girls loved the macarons at , the very real Madison outpost of the renowned Parisian patisserie; you too can enjoy their raspberry, salted caramel and pistachio flavors. You might see real students (and their parents) pop in for croissants or hazelnut cake, or, a few blocks north, perusing the mille crêpes and strawberry shortcake at the equally beloved .End the day with a cocktailEveryone needs a break, and Madison's landmark luxury hotels—the , the and the —are historic gems that attract locals and businesspeople for lunch, dinner and drinks. Enjoy a cocktail at the , which featured in Succession (it's also a popular spot for pre–Met Gala drinks), or grab lunch at the exclusive —you may spy the odd celebrity or two. in the Carlyle is classic old-school New York City, plastered with Ludwig Bemelmans' gold-tinted murals of his kids' book character Madeline in Central Park. Grab dinner in the equally venerable , with its own gorgeous murals by Marcel Vertès and live accompaniment by famous jazz bands.