MauiGuidebook.com Part of Makena State Park, One’uli (also called Naupaka Beach) is found on the Wailea side of the Pu’u Ola’i cinder cone, a prominent geological landmark feature which can be seen from points up and down the coast. Appropriately, oneuli means “dark sands” in Hawaiian. While this is the closest black sand beach to the resort areas, most visitors (and many residents) only associate black sand with Wainapanapa State Park.
Unlike typical beach sand, which is make up of ocean-ground coral and shells, black sand is made up of ground lava. On this beach, the geologic story is laid out right before your eyes; the sand is ground from a giant cross-section of the pu’u that has been dramatically cut away by the ocean. Besides clearly illustrating how the sand came to be, the exposed layers of cinder and lava also provide an unusual opportunity to view the makeup of a cinder cone.
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