Oahu offers many tour options to experience its natural beauty and history, including sightseeing tours around Honolulu focusing on WWII sites, royal palaces from Hawaii's past, and scenic landscapes. Air tours like helicopter rides provide stunning aerial views of landmarks such as Diamond Head volcano and Hanauma Bay, as well as beaches, valleys, and coral reefs visible below the clear ocean waters. In addition to structured tours, visitors can enjoy ocean activities like swimming, snorkeling at spots renowned for marine life like Hanauma Bay Nature Preserve, and scuba diving at locations frequented by sharks and rays.