Ahalanui Pond
Pahoa, HI
Ahalanui Pond is a spring fed, naturally warmed pool right where a lava rock wall meets the open ocean in Puna, the water sitting a few degrees above typical ocean temperature thanks to geothermal heat rising from below. Families spend hours here in a way they don't at colder beaches nearby, floating in warm water while waves occasionally splash over the rock wall from the sea just beyond.
The warm water genuinely sets it apart from every other swimming spot on the island, though the pool is small enough that a busy weekend can mean shoulder to shoulder company.
How we score beachesGo on an incoming tide if you want the pool a little cooler and more active. Slack tide leaves it warmer and stiller, closer to a bath than the ocean.
A free county lot serves the park off Highway 137 and can fill on weekends.
A short, paved path with steps leads down to the pool, manageable for most visitors, though the entry ladder into the water itself takes some care.
Leashed dogs are allowed in the park's grassy areas, though check current signage near the pool itself.
Puna stays warm and wet year round, and the pool's geothermal warmth makes it a comfortable swim even on a rainy day, unlike most beaches on this coast.
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