Dallas

Dallas needs 2 days: riding up Reunion Tower, the 170-meter geodesic sphere with 360-degree views over downtown, on one, and touring the Perot Museum of Nature and Science, with its futuristic facade and halls devoted to energy and Texas dinosaurs, on the other. March-May and October-November bring the mildest weather, avoiding the extreme heat of the Texan summer. It's mid-to-upper priced, with a skyscraper downtown comparable to much larger cities. It was the site of John F. Kennedy's assassination in 1963, an event that shaped its international image for decades, and today it hosts corporate headquarters for more Fortune 500 companies than almost any other US city.