Sheraton Caverns

Sheraton Caverns on Kauai's south shore in the Po'ipu resort area is named for its proximity to the Sheraton Kauai hotel complex on one of the Garden Island's finest stretches of coast—a site where submarine lava tubes and cavern formations accessible from shore create a distinctive diving experience that combines the tropical Hawaiian reef character with the geological drama of cavern diving in volcanic rock. Kauai's south shore, sheltered from the trade wind swell by the island's geography, maintains calmer conditions year-round than the north and east shores, making Po'ipu one of the most reliably diveable sections of the Hawaiian coast. The caverns at this site are lava tubes—the characteristic volcanic geology of the Hawaiian Islands expressed in its submarine form. When lava flows entered the ocean during Kauai's volcanic period millions of years ago, rapidly cooled outer surfaces formed solid crusts around still-flowing lava cores. When the lava eventually drained from these tubes, hollow passages remained—passages that were subsequently submerged as the Pacific Plate carried the island away from its volcanic hot spot source and the island gradually subsided. The result is a submarine cave system formed not by carbonate dissolution like Florida's springs but by the cooling and drainage of volcanic rock. Diving through Sheraton Caverns' lava tube passages creates an experience distinct from reef diving or even Caribbean cavern diving. The black basalt of the tube walls, sometimes smooth from the original lava flow and sometimes rough from subsequent wave erosion, frames a cavern environment illuminated from the tube's ends and openings. Fish that prefer shelter inhabit these spaces with the instinctive appreciation for enclosed habitat that governs territorial behavior in reef ecosystems—whitemouth moray eels coil in crevices along the tube walls, schools of bigeye sweep through the passages in formation, and the bottom of the tube harbors the invertebrate community of a Hawaiian subtidal rocky habitat. Hawaiian green sea turtles use the Po'ipu area extensively as habitat, and Sheraton Caverns is one of the sites where turtle encounters occur with regularity—these animals moving through the same lava tube passages that divers explore, their large bodies navigating the volcanic rock with surprising grace. The honu's underwater behavior near cavern entrances—hovering near the opening, peering into the tube with the contemplative expression that makes turtles so endearing to underwater observers—creates encounters that combine the geological drama of cavern diving with the wildlife quality of Hawaiian turtle conservation success. The Po'ipu resort area's dive infrastructure makes Sheraton Caverns accessible to visiting divers through multiple local dive operations offering guided cavern tours. For visitors to Kauai's south shore who may have come primarily for the island's famous landscape and hiking, the caverns provide an equally extraordinary underwater dimension to the Garden Island experience.