A derogatory term used to describe rush hour traffic in and around the Salt Lake City area.

Utah's highways are shitty and inadequate. Also, Utah drivers are traditionally dumb-ass, inconsiderate assholes. Everyone (EVERYONE) drives well above the posted limit of 65mph.
"I would have gotten here sooner but I got trapped in The Mormon 500."

"We left at 2:00 as to avoid The Mormon 500."
by NegativeJZ January 27, 2008
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