Oahu, Hawaii Oahu is the epicenter of Hawaii's tourism industry. The state's most populous island, it holds a majority of the resorts and most of the islands' tourist traffic. However, once you head offshore and drop below the waves of the Pacific, the tourist hordes disappear. In fact, with its wealth of dive shops and resorts that offer scuba tours, Oahu is an ideal place for both novices and experienced divers. The sheer number of dive sites (from wrecks to reefs.