More than 2,600 people have said they're interested in the event, which is set for Sept. 20 between 3 a.m. and 6 a.m. The event is meant to parody "Storm Area 51," a prank on Facebook that's attracted more than 1 million interested people.
"Blackbart can't stop us all," the Storm Casa Bonita Facebook event jokes.
"We will all meet up at the fountain and coordinate our entry," the event page says. "If we Cartman run, we can move fatter than their bullets. Let's see them Divers!"
Casa Bonita has been a staple restaurant in metro Denver since the 1970s and features Black Bart's secret hideout and performances by cliff divers. The restaurant gained national attention after it was featured on the television show South Park several years ago.
Denverites have embraced Casa Bonita, which is known for being tacky and iconic. Inside is a whimsical Mexican fiesta universe that includes an indoor lagoon surrounded by dining customers who watch cliff divers make their jumps.
The Area 51 site is part of the vast Nevada Test and Training Range and has become the center of UFO conspiracy theories.
That Facebook event jokes, "They can't stop all of us," and "Let's see them aliens."
The U.S. Air Force has warned people against participating in the internet joke.
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