Spouting Horn, Natural blowhole on south shore of Kauai, US.

Spouting Horn is a blowhole on the south shore of Kauai where ocean waves crash into an underground lava cavity and force water up through a narrow opening in the rock, sometimes reaching 15 meters high. The site has paved walkways, information panels, free parking, and local craft vendors set up nearby.

The blowhole formed where waves erode lava rock along Kauai's southern coast, creating a narrow opening through which water is forced upward. The Hawaiian name puhi, meaning blowhole, records the feature in the local language. The site is now a stop on the 10-mile Koloa Heritage Trail through the Koloa district.

The Hawaiian name puhi means blowhole. In local folklore a giant mo'o, a lizard, chased the young man Liko through a lava tube and became stuck in the opening; the hiss of each wave is heard as the creature's roar. The site lies on the 10-mile Koloa Heritage Trail.

The spray rises highest when ocean swells are strong, so check surf conditions before going; in flat weather the plume is small. The blowhole sits along the 10-mile Koloa Heritage Trail in the Koloa district, and the viewing area is reached on foot. Stay on the paved path, as the jagged lava rocks at the base are wet and slippery.

The original Hawaiian name for the site was puhi, meaning blowhole. The Spouting Horn is one stop on the Koloa Heritage Trail, a 10-mile route through the Koloa district. In the legend, the hissing blast is the roar of a giant mo'o, a lizard that chased the young man Liko into a lava tube and became stuck there.