Couple Discovers Huge Lava Cave Below Their Home in Oregon

A large lava tube—a cave formed from a volcanic eruption—was discovered beneath a home in Bend in central Oregon.

Back in 2017, realtors told Suzanne and James Brierley that there was a small cave somewhere below their home when they purchased the 10-acre property that year. But the homeowners were surprised to recently discover how large the cave was.

"I was really shocked by how big it was... You couldn't even touch the ceiling in it," James told Bend's KTVZ.

"It was quite impressive, it was kinda like a gift we didn't really know we'd had," he added.

The Brierleys contacted Oregon High Desert Grotto, a branch of the National Speleological Society, in a bid to establish the origins of the lava tube.

The cave was examined by members of the caving club who collected data from the site. There are still areas of the cave that have yet to be explored, according to the club, KTVZ reported.

The Brierleys, whose property is currently up for sale, hope the future homeowners will help preserve the cave.

Newsweek has contacted Oregon High Desert Grotto and the National Speleological Society for comment.

Lava tubes are probably the second most common type of cave, after limestone caves, the U.S. National Park Service (NPS) says, and most are found "close to [the] surface and not too deep underground."

Lava tubes form from lava, which is "thousands of degrees hot and can flow like a river," flowing through an area.

The NPS explains: "The top of this white-hot river will cool with exposure to the much colder temperatures in the air above. As it cools the lava solidifies into black stone while down below the molten river keeps flowing.

"The rock above keeps cooling. It thickens and widens and will finally form a roof across the molten rock below creating the ceiling of the cave. Eventually as the eruption ends or the lava flow moves to someplace else, the lava tube drains of molten rock leaving a cave tunnel behind," the NPS adds.

There are believed to be as many as 400 lava tubes in central Oregon, many of which are on public lands, according to the Bend tourism website.

"These caves were formed by molten lava when the Newberry Volcano erupted and the lava flowed north," the website says.

The Lava River Cave system, the "longest, continuous lava tube in Oregon", is located off Highway 97 next to Oregon's Lava Lands Visitor Center, the Bend tourism website says.

Hawaii is home to some of the world's longest lava tubes. Kazumura, a lava tube on the Big Island of Hawaii, is the deepest cave in the U.S.

The lava tube begins at Hawaii Volcanoes National Park. It extends miles beyond the park border, running downhill from the Kilauea Volcano.

The NPS says: "The Kazumura Cave has been mapped to a length 40.7 miles long and a depth of 3,614 feet, making it one of the most significant lava caves on Earth."

Hawaii's Thurston Lava Tube seen in 2016
The Thurston Lava Tube pictured in December 2016 at the Volcanoes National Park in Hawaii, which is home to some of the world's longest lava tubes. A couple in Oregon discovered a large lava tube beneath their home in Bend. George Rose/Getty Images