Waikiki Aquarium, 2777 Kalakaua Ave, ☎ +1 808 923-9741, [4]. Daily 9AM-4:30PM, closed 25 Dec. The third oldest aquarium in the U.S., this incredible institution has hundreds of species of marine life from Hawaii and the Pacific, including sharks, octopus, jellyfish, colorful reef fish, coral, and an outdoor exhibit with Hawaiian monk seals. $9, $6 residents/military/students/seniors, $4 teen, $2 children, under age 5 free.