Founded in 1904 with 35 tanks, and 400 marine organisms, the Waikiki Aquarium is the second oldest public aquarium in the United States. It was built next to a living coral reef on the Waikiki shoreline, and is now home to more than 3,500 organisms of 490 species of marine plants and animals.
The Waikiki Aquarium has been an institution of the University of Hawaii since 1919, and every year, more than 330,000 individuals visit the aquarium. An additional 30,000 school children participate in educational activities and programs developed by the aquarium as part of their involvement in the Coastal Ecosystem Learning Center of the Coastal America Partnership federal program.
Fun fact: the aquarium was established by the Honolulu Rapid Transit authority with a purpose of enticing travelers to ride the trolley to the end of the line at Queen Kapiolani Park. I guess it was successful, because more than 100 years later, the aquarium is a wildly popular Honolulu destination for local families and tourists alike.