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Hōlei Sea Arch facts for kids

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Hōlei Sea Arch
Location Big Island, Hawaii, United States
Nearest city Kalapana, Hawaii
Elevation 90 ft (27 m)
Hōlei sea arch
View of Hōlei Sea Arch in 2010

The Hōlei Sea Arch was a famous 90-foot-high (27-meter) natural arch located in the United States. It stood on the southern shore of the Big Island of Hawaiʻi. You could find it inside Hawaiʻi Volcanoes National Park at the end of the Chain of Craters Road. The arch was made of dark volcanic rock called basalt. Powerful ocean waves carved it from an old lava flow about 550 years ago. In late September 2026, this amazing rock formation finally collapsed into the sea.

How the Hōlei Sea Arch Formed

Volcanoes like Kīlauea helped build the Hawaiian islands. When hot lava flowed into the cold ocean, it cooled quickly into tough rock. Over hundreds of years, strong waves continuously crashed against the sea cliffs.

This wearing away is called differential erosion. Water breaks down softer rock much faster than harder rock. First, the ocean hollowed out sea caves in the cliffs. Over time, waves punched all the way through, leaving behind a magnificent stone bridge over the water.

Why Did the Natural Arch Fall?

Sea arches are exciting shapes, but they do not last forever. The National Park Service knew the cliffs were unstable. In 2018, earthquakes from a Kīlauea eruption shook the area and created deep cracks.

Huge ocean waves in 2022 broke away chunks of rock from the base. Park rangers kept visitors safely away from the dangerous cliff edges. Finally, after stormy seas around the time of Hurricane Nolo, the arch fell into the Pacific Ocean in September 2026.

See Also

  • Aruba Natural Bridge
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