Kialo Winters was leading a tour of the Valley of Dreams trail, near the Ah-Shi-Sle-Pah Wilderness in north-west New Mexico, on 30 October when he came around a corner and found one of the area’s most famous spires reduced to rubble.

“We turned the corner, and my heart just dropped,” Winters said.

The formation, known as the Alien Throne, is one of the undulating, gravity-defying rock spires — hoodoos — that draw visitors and photographers to the landscape of the US south-west. It is featured prominently on a local tourism website.

“The highlight feature that everyone wants to see is the Alien Throne,” Winters said.

Winters has guided visitors to the region for 13 years as part of Navajo Tours USA, a company he founded. He said he immediately assumed the heavy rains and the super El Niño season were to blame for the collapse.

A week before the discovery, rainstorms and flooding hit north-west New Mexico hard, forcing evacuations and hundreds of water rescues of stranded residents. In Farmington, the nearest town to the Valley of Dreams area, some families spent the night on rooftops watching the river flood their homes before they were rescued, officials said.

As communities in the Four Corners region struggle with the aftermath of flooding, washed-out roads and damaged homes, more damage to the region’s natural wonders may still be discovered.

The rock spires sit on Navajo Nation land. They are beloved by visitors and photographers, Winters said, but they also carry a deeper significance for the region’s Indigenous residents.

“They are traditional waypoints in our Indigenous history that have guided our people across the land for many generations,” he said.

The Alien Throne was not the only formation to come down. Winters said another nearby formation, the King of Wings — what he called “the unicorn of hoodoos” — has also been damaged in recent weeks. Multiple user posts on AllTrails, a hiking website, suggested that formation had broken sometime before 9 October, before intense rains hit the region.

“Those are heavy losses for us,” Winters said.

He added: “The land is alive, and we understand it changes. The same erosion that made them also brings them down, that is what our elders tell us.”

Winters said his assumption is that the Alien Throne broke because of “natural causes,” but the Navajo Nation and the Bureau of Land Management are expected to examine the site and confirm the cause.

It is not yet clear how much damage may have been done to other rock spires across the Four Corners region of Utah, Colorado, Arizona and New Mexico during the past weeks of heavy rain and flooding. Park rangers at the Chiricahua, Goblin Valley, Gold Butte and Cathedral Gorge state and national parks, which have extensive hoodoo formations, told SFGate they had not yet documented any damage.

In a super El Niño year of ongoing intense storms in the Pacific, famous rock formations across time zones are showing damage. Earlier in October, Hawaii’s centuries-old Hōlei sea arch collapsed into the Pacific.

Winters called on visitors to the damaged spires to “let that site rest” — not to climb what is left of the formations, and not to take stones home as relics.

“It’s illegal to do that,” he said, adding: “It’s disrespectful to the community as a whole.”

“We’ll keep honoring those sentinels and waypoints through story and photographs and art installations,” Winters said of the lost formations on Navajo Nation land. “Their legacies live on.”