Chicago

Chicago needs 3 days: Millennium Park and its famous «The Bean» sculpture on one, the Loop's architecture (with a river boat tour) on another, and a museum (Art Institute or Field Museum) on the third. June-September brings the best weather, since winters are among the coldest of any major US city. Prices are moderate for a city its size, more affordable than New York or San Francisco. It's world-renowned for its architecture: it was the birthplace of the modern skyscraper after the Great Fire of 1871, and today its architectural boat tours are among the country's most recommended.