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.

Second only to Berlin in size and population, the city of Hamburg is home to one of the biggest harbors in Europe. A stroll along its many waterways and canals illustrates why it has been called the "Venice of the North." Don't miss a trip to the local fish market (Fischmarkt), the Merchants District (marked by its imposing red-brick architecture), a fine dining experience along the river or a night out in the university quarter. And did we mention the Reeperbahn (red light district)? It's quite famous for its… red lights.

So many of Madrid’s buildings look like castles, you’ll think you’ve stumbled into a fairytale. Even City Hall is astounding, with its white pinnacles and neo-Gothic features. A self-guided architecture tour can begin by the great bear statue in the central Puerta del Sol. Wander by the fanciful Royal Palace before absorbing the natural beauty of Retiro Park, then visit one of the city’s many museums. You could happily cap off each day by nibbling on forkfuls of paella while sipping Spanish rioja.

Once known for smog, traffic and tacky architecture, Athens is a city reformed thanks to fortunes brought by the 2004 Summer Olympics. Spotless parks and streets, an ultra-modern subway, new freeways, an accessible airport and all signs in perfect English make the city easily negotiable. Meriting more than a stopover en route to the islands, sophisticated Athens sites include many pillars of Western history, from the Acropolis to the Temple of Olympian Zeus, as well as treasures in the National Archaeological Museum.

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.

Vancouver was founded as “Gastown” by an Englishman with a penchant for beer and storytelling. Today Gastown is a historic section of the Canadian metropolis, and the lively pubs still reflect the area’s former status as a sort of community drinking center. The city’s forests, grand parks, and impressive suspension bridge beckon travelers to explore them, as do the city’s shops and museums. Relive the glory of the 2010 Winter Games with visits to Olympic venues and the marvelous Olympic Cauldron.

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.

Atmospheric backstreets paint a very different picture to first impressions of Abu Dhabi. The often slick and modern capital of the U.A.E. presents a fascinating mixture of tradition and progression. Tracing its rich history back to around 3000 B.C., Abu Dhabi maintains a more distinctly Arabian ambiance than glitzy Dubai. Taxis are a safe, reliable way to get around sites such as The Corniche Park, the White Fort, the Heritage Village, which offers glimpses into Bedouin life, and the Women's Craft Centre.

Every neighborhood in San Francisco has its own personality, from the hippie chic of the Upper Haight to the hipster grit of the Mission. The Marina district boasts trendy bistros and postcard-perfect views of the Golden Gate Bridge, while Noe Valley offers quaint and quiet boutiques. Wave hello to the sea lions at Pier 39, and sample local cheese and charcuterie at the Ferry Building. Sit in on a yoga session in Dolores Park or marvel at the Dutch Windmill across from Ocean Beach.

Hollywood beckons to tourists who long for a brush with Tinseltown glamor. Tour movie studios, slip your hands into the famous prints at the TCL Chinese Theatre, or indulge in a celeb sighting at one of LA’s white-hot nightspots. Spot your favorite star while shopping at The Grove, or forget all about the famous eye candy as you take in the iconic artwork at The Getty Center. For a different type of star-gazing, peek through the telescopes at the Griffith Observatory.