New York City

New York needs 4 days: Manhattan (Times Square, Central Park, museums) takes up most of it, plus at least one trip to Brooklyn. April-June avoids winter cold and the heavy humidity of July-August. It's one of the world's most expensive cities, with hotel rates double those of other major American capitals. It's the most populous city in the US, with iconic skyscrapers, Broadway and a cultural diversity where over 800 languages are spoken — more than in any other city on the planet.