Things to do nearHanauma Bay

Hanauma Bay was formed roughly 32,000 years ago when volcanic activity created a tuff cone that the ocean eventually breached, carving out the sheltered cove visible today. The Hawaiian name is thought to mean curved bay, a fitting description for the bay's distinctive horseshoe shape. In 1967 it was designated a Marine Life Conservation District, one of the first in Hawaii, and the site has since become a model for balancing public access with ecological preservation.

The reef system inside Hanauma Bay supports hundreds of species of fish along with green sea turtles, octopuses, and a variety of corals. The inner reef area known as the Keyhole offers calm, shallow water well suited to first-time snorkelers, while more experienced swimmers venture toward the outer reef where the marine life grows more varied and the coral formations more dramatic. Fins, masks, and snorkels are available for rent near the beach.

Above the waterline, the bay's surrounding crater walls are laced with hiking trails that offer sweeping views back over the cove and out toward Koko Head and the Koolau Range. The visitor center at the top of the hill houses educational exhibits on Hawaiian marine ecosystems and the geology that shaped the bay.

Hanauma Bay stands apart from other snorkeling destinations in Hawaii because of the genuine care taken to protect it, giving visitors the rare experience of a thriving reef that has been allowed to recover and flourish over decades.