First it was Utah. Then Romania. And California. Spain. Wales. Paraguay.

The metallic monoliths began to be found in late 2020 by unsuspecting viewers in seemingly random locations around the world.

Often evocative of a science fiction movie prop, the mysterious objects captured the public’s attention and frequently drew crowds hoping to catch a glimpse of the bewildering columns.

Then, earlier this month, another gleaming prism materialized outside of Las Vegas.

“We see a lot of weird things when people go hiking like not being prepared for the weather, not bringing enough water... but check this out!” the Las Vegas Metropolitan Police Department said in a post on X.

Police say they don’t know who is responsible for the monolith or how they got it there.

Just what, exactly, are these things? Some have speculated they’ve been deposited on Earth by alien visitors. Others surmise the monoliths might be far-out works of art — or simply playful pranks.

The first monolith appeared in Utah in 2020

In November 2020, the Utah Department of Public Safety announced that a group of workers conducting a count of bighorn sheep noticed a reflective object in a remote section of “red rock country.”

Photos showed the eerie metallic monolith standing before what looked like a rocky Martian landscape.

Utah officials didn’t disclose the location of the object, given that it was extremely remote and lacked resources like restrooms, but onlookers flocked there anyway.

The U.S. Bureau of Land Management said later that month that the monolith had been removed over Thanksgiving weekend by an unknown person or group. Tire tracks and human waste had been left behind, and more than one vehicle had to be towed out.

In the days and weeks that followed, monoliths began to pop up around the world — atop a California mountain, in the ruins of a Spanish church, on the hills of a New Zealand adventure park.

A monolith that arose in the Romanian city of Piatra Neamt was welcomed by the city’s mayor, Andrei Carabelea, who joked about the object’s puzzling origins in a statement on Facebook.

“My guess is that some naughty, terrifying alien teenagers left home with their parents' UFO and started planting metal monoliths around the world,” Carabelea said in the statement translated from Romanian.

According to the website MonolithTracker.com, there have been a total of 245 monoliths reported worldwide since late 2020.

Another object was discovered outside Las Vegas this month

On June 17, Las Vegas authorities announced that a local volunteer search-and-rescue team had spotted a shiny, metallic monolith near Gass Peak in the Desert National Wildlife Refuge north of the city.

The Las Vegas Metropolitan Police Department posted photos of the object online and urged people to be safe outdoors “[w]hile the internet gets to work on this mystery.”

Standing at six feet, five inches tall and 13” wide on each of its three faces, the monolith was made of folded sheet metal and held together with rebar and concrete, authorities said.

Four days later, the police department said it had helped remove the monolith “due to public safety and environmental concerns.” It is being stored at an undisclosed location.

The U.S. Fish & Wildlife Service thanked the LVMPD for its assistance in locating and removing the monolith and warned visitors to the remote area to be prepared for rough terrain and no water or cell service.

Who’s behind the monoliths?

Whoever created the Utah monolith, which seems to have kicked off the monolith frenzy in recent years, remains unknown.

David Zwirner, a gallerist who represents the estate of the late artist John McCracken, initially told The New York Times that he believed the object was created by McCracken. But Zwirner later retracted that assertion after getting a closer look at the monolith and seeing that it was machine-made, which was not McCracken’s style, Vox reported.

An artist collective known for lampooning popular culture called the Most Famous Artist seemed to take credit for the Utah monolith, Mashable reported in late 2020, and began selling a monolith on its website for $45,000.

Others think it could be a Hollywood prop. According to Gizmodo, the monolith was found near Dead Horse Point State Park, which was a shooting location for multiple TV shows and films in recent years, including HBO’s Westworld and the 2012 sci-fi movie John Carter.

Some people have taken credit for other monoliths, suggesting that the original object in Utah likely inspired copycats around the world.

To this day, mystery surrounds the Utah monolith and many of its successors, perhaps adding to their appeal. But the truth, though we may not know it yet, is out there.

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