Swedish students collectively scream every night at 10 p.m.

If you screamed as loud as you could from a window tonight, you’d probably receive several invitations to shut the heck up, but but not in the Flogsta neighborhood of Uppsala, Sweden. As this video creepily demonstrates, this community has a daily ritual called "the Flogsta scream" in which each night at 10 p.m., students scream collectively from windows, balconies and rooftops. Its origin is debated: Some say it’s a stress relief technique that emerged during exam times and became a daily habit. Others say it began as a remembrance of a student’s suicide in the 1970s. We're betting some outsiders might admit that the first time they heard it, they needed new pants.

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