Rome wasn't built in a day--and you'll need much more than a day to take in this timeless city. The city is a real-life collage of piazzas, open-air markets, and astonishing historic sites. Toss a coin into the Trevi Fountain, contemplate the Colosseum and the Pantheon, and sample a perfect espresso or gelato before spending an afternoon shopping at the Campo de’Fiori or Via Veneto. Enjoy some of the most memorable meals of your life here, too, from fresh pasta to succulent fried artichokes or a tender oxtail stew.

Over the centuries, many cultures have added their mark to this prized piece of land. Today, you can experience those influences firsthand by exploring Istanbul’s mahalles (neighborhoods). From the holy sites of Sultanahmet and the 19th-century European elegance of Beyoğlu to the high fashion of Nişantaşı, the vibrant café society of Kadıköy and the football-loving streets of Beşiktaş, it’s easy to see why travelers say that Istanbul isn’t just one city, but many cities within one.

Lingering over pain au chocolat in a sidewalk café, relaxing after a day of strolling along the Seine and marveling at icons like the Eiffel Tower and the Arc de Triomphe… the perfect Paris experience combines leisure and liveliness with enough time to savor both an exquisite meal and exhibits at the Louvre. Awaken your spirit at Notre Dame, bargain hunt at the Marché aux Puces de Montreuil or for goodies at the Marché Biologique Raspail, then cap it all off with a risqué show at the Moulin Rouge.

Barcelona feels a bit surreal – appropriate, since Salvador Dali spent time here and Spanish Catalan architect Antoni Gaudí designed several of the city’s buildings. Stepping into Gaudí’s Church of the Sacred Family is a bit like falling through the looking glass - a journey that you can continue with a visit to Park Güell. Sip sangria at a sidewalk café in Las Ramblas while watching flamboyant street performers, then create your own moveable feast by floating from tapas bar to tapas bar.

From Shoreditch’s swaggering style to Camden’s punky vibe and chic Portobello Road, London is many worlds in one. The city’s energy means that no two days are the same. Explore royal or historic sites, tick off landmarks from your bucket list, eat and drink in exclusive Michelin-starred restaurants, enjoy a pint in a traditional pub, or get lost down winding cobbled streets and see what you stumble across – when it comes to London, the possibilities are endless.

Dubai is a destination that mixes modern culture with history, adventure with world-class shopping and entertainment. Catch a show at the Dubai Opera, see downtown from atop the Burj Khalifa and spend an afternoon along Dubai Creek exploring the gold, textile and spice souks. If you’re looking for thrills, you can float above the desert dunes in a hot air balloon, climb aboard a high-speed ride at IMG Worlds of Adventure or skydive over the Palm Jumeirah.

Walk the Freedom Trail the first time you visit Boston and you'll quickly get a sense of this coastal city's revolutionary spirit and history. But make sure you also explore some of Boston's fine museums (try the Isabella Stewart Gardner, featuring masterpieces displayed in their collector's mansion) and old neighborhoods (like the North End, Boston's Little Italy). You can't claim to have experienced real Boston culture, though, until you've watched a Red Sox game from the bleachers.

Conquering New York in one visit is impossible. Instead, hit the must-sees – the Empire State Building, the Statue of Liberty, Central Park, the Metropolitan Museum of Art – and then explore off the beaten path with visits to The Cloisters or one of the city’s libraries. Indulge in the bohemian shops of the West Village or the fine dining of the Upper West Side. The bustling marketplace inside of Grand Central Station gives you a literal taste of the best the city has to offer.

Once a destination for honeymoons and family vacations, Niagara Falls has really stepped it up as an action-packed vacation spot. The falls are literally the biggest draw – watching the frothy water tumble at alarming speeds can be mesmerizing. Throw on a poncho and hop aboard the Maid of the Mist to cruise close enough to the falls to be drenched by spray. Hit the main strip of Clifton Hill for flashy tourist attractions and restaurants galore.

Hershey, Pennsylvania, the home of the Hershey Chocolate Company, bills itself as "The Sweetest Place on Earth," and it's hard to imagine another city giving it a run for its money. The city was built on chocolate, as were the great majority of its attractions. Hershey's Chocolate World takes sweet tooths on a virtual tour of the Hershey factory, and Hersheypark allows kids and adults alike to frolic through a vast land of rollercoasters, waterslides and walking, life-sized chocolate bars.