The only city in the world that can lay claim to straddling two continents, Istanbul—once known as Constantinople, capital of the Byzantine and then the Ottoman Empire—has for centuries been a bustling metropolis with one foot in Europe and the other in Asia. Istanbul embraces this enviable position with both a certain chaos and inventiveness, ever evolving as one of the world’s most cosmopolitan crossroads. It’s often said that Istanbul is the meeting point of East and West, but visitors to this city built over the former capital of two great empires are likely to be just as impressed by the juxtaposition of old and new. Office towers creep up behind historic palaces, women in chic designer outfits pass others wearing long skirts and head coverings, peddlers’ pushcarts vie with battered old Fiats and shiny BMWs for dominance of the noisy, narrow streets, and the Grand Bazaar competes with modern shopping malls. At dawn, when the muezzin's call to prayer resounds from ancient minarets, there are inevitably a few hearty revelers still making their way home from nightclubs and bars. Most visitors to this sprawling city of more than 14 million will first set foot in the relatively compact Old City, where the legacy of the Byzantine and Ottoman empires can be seen in monumental works of architecture like the brilliant Aya Sofya and the beautifully proportioned mosques built by the great architect Sinan. Though it would be easy to spend days, if not weeks, exploring the wealth of attractions in the historical peninsula, visitors should make sure also to venture elsewhere in order to experience the vibrancy of contemporary Istanbul. With a lively nightlife propelled by its young population and an exciting arts scene that’s increasingly on the international radar—thanks in part to its stint as the European Capital of Culture in 2010—Istanbul is truly a city that never sleeps. It’s also a place where visitors will feel welcome: Istanbul may be on the Bosphorus, but at heart it’s a Mediterranean city, whose friendly inhabitants are effusively social and eager to share what they love most about it.