Oahu is a melting pot of cultures, and its capital city, Honolulu, is a hub of historical and cultural sites. One of the most iconic attractions is Diamond Head, which is a dormant volcano that overlooks Waikiki. Its WWII pillboxes and tunnels lead up to a lookout point which overlooks pristine surfing beaches as well as jungly mountains.. The Iolani Palace, the only royal palace in the United States, offers insights into Hawaii’s monarchy and history. The Bishop Museum showcases Polynesian culture and history, featuring exhibits on traditional art, artifacts, and the islands’ natural history.