Whether you're a long-time resident or a visitor, a certified diver or a beginning snorkeler, this guide to twenty-six of O'ahu's best snorkeling and diving sites will enrich and enhance your underwater adventures. Detailed driving directions to each location are included as well as helpful maps showing onshore facilities and many offshore features you'll want to explore. You'll learn where it's safest to enter and exit the water, what to look for (coral, shells, fishes, underwater caverns), and what hazards to avoid. The author provides essential information on safety and seasonal wind and surf conditions and useful tips on diving and snorkeling equipment, night diving, and spear fishing. Each site, chosen for its ease of access and the interest of its underwater topography, is rated according to degree of difficulty. The O'ahu Shore Divers' and Snorkelers Guide will introduce you to some of the best diving and snorkeling on the island.