Glamorous Santorini, in the southern Aegean's Cyclades islands, curves round a giant lagoon, a caldera left by a volcanic eruption.

The "joie de vivre" is palpable and contagious in this vibrant, culturally diverse and cosmopolitan city of two million inhabitants.

Historic and modern, European and Asian — that's Istanbul. The city at the junction of two continents is home to ancient structures like the Hagia Sophia and the Blue Mosque in the Old City, as well as modern businesses, hotels, restaurants and nightlife in the New City.

South Beach, or SoBe, is Miami Beach's buzziest bit. The vibrant area, with its pastel-hued buildings, hip nightclubs, trendy shops and see-and-be-seen restaurants, attracts socialites and their satellites year-round.