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.

It’s nicknamed the Eternal City for a reason. In Rome, you can drink from a street fountain fed by an ancient aqueduct. Or see the same profile on a statue in the Capitoline Museum and the guy making your cappuccino. (Which, of course, you know never to order after 11 am.) Rome is also a city of contrasts—what other place on earth could be home to both the Vatican and La Dolce Vita?

To the first-time visitor, Palermo is a city of ever-changing character. An abundance of dusty museums, Arabian domes and flourishes of baroque splendor jostle with boisterous markets, chaotic traffic and oppressive summer heat. The Sicilian hotspot is a noisy, polluted, often dangerous, but always fascinating city. Don't miss marvels of Arab-Norman architecture, such as 12th-century Palazzo dei Normanni or San Giovanni degli Eremiti. Ask your hotel to arrange cabs and negotiate fares before setting off.

Laid out by British architect Edwin Lutyens, the Indian capital is a striking modern metropolis. A gracious contrast to Old Delhi's winding streets, the grand avenues and stately buildings of New Delhi are rich with history and culture, from Gandhi's Delhi home (and the site of his assassination) to the tomb of Humayun, a complex of Mughal buildings reminiscent of the Taj Mahal. Chaotic traffic is best left to the locals. Negotiate a good price for taxis or travel on the new Delhi Metro.