Honolulu

Honolulu needs 3 days: Waikiki Beach and Diamond Head (a volcanic crater with a trail to the summit) on one, the USS Arizona Memorial at Pearl Harbor on another, and a trip to Oahu's east coast (Hanauma Bay for snorkeling) on the third. April-June and September-October avoid winter rains and summer vacation crowds. It's expensive, among the priciest US cities due to its island status -almost everything is shipped or flown in. It's the capital of Hawaii and the only US city attacked by a foreign power in the 20th century, a fact that still shapes its identity through the Pearl Harbor memorial.