Claim:
In December 2025, a mountain west of Casper, Wyoming, collapsed into itself.
Rating:
In December 2025, a dramatic image and story about a Wyoming mountain captured the attention of many people online. One Facebook post (archived) with tens of thousands of likes described how “an entire unnamed mountain” west of Casper, Wyoming, collapsed inward on Dec. 5, forming a massive crater and leaving some people missing. The post also included an image that appeared to show a dirt road full of cars next to a pine tree-covered mountain with a crater in place of one of its faces.
The full text of the post read:
Wyoming Mountain Collapses Into Itself, Area Closed as Search Crews Mobilize
Casper, WY – A geological event that experts are already calling “one of the strangest in modern history,” an entire unnamed mountain west of Casper reportedly collapsed inward early Friday morning, forming a massive crater and sending shockwaves through surrounding communities.
Local ranchers said they heard what sounded like a “deep thunderclap underground” just before the peak seemed to sink straight down, leaving behind a bowl shaped void nearly a mile wide. Emergency officials quickly closed the region to the public as reports surfaced of at least two hiking groups believed to have been in the area at the time.
Wyoming Conservation Services, Natrona County Emergency Management, and search and rescue teams from across the state are already on scene, with additional specialized crews from Colorado, Montana, and Idaho currently en route. Federal geological teams are also being deployed to determine whether the collapse was caused by seismic activity, a long hidden cavern system, or something “significantly more unusual,” according to officials.
Residents across central Wyoming reported feeling the tremor, with some describing a brief vibration followed by a low rumble that lasted nearly ten seconds.
Authorities are urging the public to avoid the area entirely until stability assessments are complete. Officials say the primary focus now is locating potential survivors and securing the perimeter around what one responder described as “a mountain that folded like a camp chair.”
More updates will be released as information becomes available.
That post and image were shared on blogs (archived) and on other social media sites, such as X (archived). Some people in the comments and replies of these various posts appeared to believe the claim was true. A Snopes reader sent us an email asking whether the rumor was true.
The story wasn’t real. It was posted online by a page that describes its content as satirical.
A Google search for “wyoming mountain collapse” limited to results from the days around the supposed collapse returned no credible reporting on the event. Considering this purported event caused missing people, it would’ve at least been reported by local news sources.
While the Casper Planet (archived), the Facebook page that first reported the collapse, may at first sound like a local news source, it is in actuality a satirical page. Casper Planet’s Facebook intro read:
Delivering the Snews that doesn’t matter directly to your Snews feed. Did we say this is satire? Well it is, names/locations are made up
Casper Planet included some hints to the story’s fictional nature within the post itself. For example, the post referenced the Wyoming Conservation Services, which is an agency that doesn’t actually exist. Casper Planet regularly uses fake agency and organization names that sound similar to real ones; Wyoming Conservation Services, which has a similar name to the real-life Wyoming Conservation Corps, has been referenced in some of Casper Planet’s other posts, including a prior one fact-checked by Snopes.
The page even updated the story with a follow-up post (archived) that shared missing-person sketches that resembled Waldo from the “Where’s Waldo?” books and actor Danny DeVito.
The image that accompanied Casper Planet’s story was not real, either, as there was evidence it was generated by artificial intelligence tools.
The most obvious indication of this could be seen by examining the cars along the dirt road, all of which were deformed; AI tools sometimes struggle with depicting finer details within images. Another hint to the image’s AI-generated origins could be seen within the landscape, as the grass within the image was green throughout and in Wyoming the grass is usually brown by December. Even in the fall, images from the Casper Area Convention and Visitors Bureau show the grass has mostly turned brown by then.
However, while this particular mountain collapse was fictional, mountains can collapse by landslides and mudslides, which can look similar to the collapse in the AI-generated image. The Wyoming Department of Transportation posted an image of a slide from Wyoming’s Teton Pass in June 2024 that had a crater similar to the one from the Casper Planet post. Slide-induced mountain collapses have been happening in Wyoming for millions of years, and multiple have happened in the Yellowstone area over the past century alone.
Snopes has addressed similar satirical claims from Casper Planet in the past, including a rumor from earlier this year about a wind turbine blade flying like a helicopter for 47 miles.
For background, here is why we alert readers to rumors created by sources that call their output humorous or satirical.
