"When in Rome, do as the Romans." That classic advice leads to a wealth of options: Should you follow Augustus and Caesar, whose Rome is filled with spectacular ancient structures? Or Michelangelo and Da Vinci, whose city invites artistic pilgrimage? Maybe you'll discover the Rome that enchants lovers and sightseers alike? Rome encompasses all this and more.

Say aloha to tropical breezes, oceanfront luaus and iconic Diamond Head on Oahu, the most populated Hawaiian island. Follow in the sandprints of surfing forefather Duke Kahanamoku on Waikiki Beach, visit the royal quarters of Iolani Palace and tour Pearl Harbor.

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.

Grand Cayman's splashier side is the real draw. Offering a host of experiences, from petting attention- and food-seeking stingrays at Stingray City to exploring jaw-dropping drop-offs and dive sites, Grand Cayman is a watery wonderland.