The Google Maps red pin for the Hōlei Sea Arch, a rugged, 90-foot bow formed by 550-year-old lava flows and the prolonged sculpture of the salty Pacific, now states, “Permanently closed.”
On Thursday, the National Park Service said the picturesque arch at Hawai’i Volcanoes National Park on the Big Island had collapsed sometime between Sept. 23 and Sunday, around the time a tropical cyclone sent sizable swell into the coast.
“The exact time of the collapse is unknown and could have occurred when the park was temporarily closed during Tropical Storm Nolo,” the park service said in a statement.
The park service lamented the collapse of the natural feature it said was likely rooted in lava flows roughly half a millennium ago and then slowly shaped by the reduction of a roiling sea.
It also said some who want to see what’s left of the Hōlei Sea Arch have stepped too close to the edge of surrounding cliffs — as seen on social media.
The park service warned sightseers to keep a safe distance from the eroding coastline, where they could put “themselves and first responders at great risk of falling and drowning off the rough, wave-swept coast,” it said.
“Visitors are urged to stay back from the unstable coastal cliff edges which drop off vertically into the ocean and present a serious falling hazard,” it said.
The collapse was a long time coming, the park service said, with the 2018 Kīlauea eruption shaking the ground enough to damage the arch’s neighboring cliffs.
New cracks on the feature and its surroundings in early 2020 inspired Hawai’i Volcanoes National Park officials to move the Hōlei Sea Arch’s viewing area farther from land’s end, the park service said.
“Later that year, massive surf from Tropical Storm Darby broke off a chunk of rock from the lower part of the arch,” it said.
The U.S. Geological Survey said the arch is a product of “differential erosion by ocean waves” whereby the sea works to first remove material along cracks and weaker sections of basalt rock.
“Every day the ocean crashes against the pillar of the arch, eroding it a little more,” it said in its entry for the arch. “One day, it will be gone.”