Over 15 million gallons of water bubble daily into Budapest's 118 springs and boreholes. The city of spas offers an astounding array of baths, from the sparkling Gellert Baths to the vast 1913 neo-baroque Szechenyi Spa to Rudas Spa, a dramatic 16th-century Turkish pool with original Ottoman architecture. The "Queen of the Danube" is also steeped in history, culture and natural beauty. Get your camera ready for the Roman ruins of the Aquincum Museum, Heroes' Square and Statue Park, and the 300-foot dome of St. Stephen's Basilica.

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.

This city, full of colorful homes, canals and bridges, is one of Europe's most picturesque capitals. Must-sees on any visitor's itinerary include the Anne Frank House, the Van Gogh Museum and the world's only floating flower market. Rent a bike and join thousands of locals navigating Amsterdam's labyrinthine streets, or just take in the sights on foot. For an unusual and memorable alternative to hotels, consider staying in a houseboat.

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.

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.

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.

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.

Packed with historic landmarks, bustling eateries, and manicured parks, the vibrant city of Lahore exudes culture at every corner. From soaring minarets and colorful facades to street-level stalls selling flavorful Punjabi favorites, the increasingly cosmopolitan city radiates with energy.

Known as the safari capital of Africa, Nairobi is an energetic, modern city that serves as a fascinating introduction to both wildlife and nightlife. Music clubs pulse with life, shops and markets bustle, and a mélange of restaurants will tempt your palate in this former Maasai watering hole. Top sights include the Karen Blixen Museum, Giraffe Centre and the black rhinos of Nairobi National Park. The compact city center is safe to walk in and taxis make other areas accessible.

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.