Ocean Expo Park
Will give you a better idea of the creatures native to the waters surrounding okinawa island.
beaches
Go to the island's many beaches.
Scuba diving is one of the most popular activities on the island with an abundance of dive shops across the island. Chatan and Kadena have ports leaving for the Kerama Islands. Bluefield (http://www.bluefi.com/en) and Reef Encounters (http://www.reefencounters.org) offer diving service in English.
Spear fishing is another popular activity on the island.
Take a glass bottom boat tour, offering views of corals and fishes.