Several fatal collisions in the 1990 Interstate 75 fog disaster result in a total of 12 deaths and 42 being injured

The 1990 Interstate 75 fog disaster was a traffic collision that occurred on the morning of December 11, 1990, on a section of Interstate 75 (I-75) near Calhoun, Tennessee, during dense fog which obscured the visibility of motorists. The collisions occurred in an area where fog is common and had been the site of previous multi-vehicle collisions caused by poor visibility. It consisted of a series of multi-vehicle collisions that ultimately involved 99 vehicles, and resulted in 12 deaths and 42 injuries. It was reportedly the largest motor vehicle collision in United States history when it occurred, in terms of the number of vehicles, and was the largest and second deadliest vehicle accident in Tennessee history behind the 1972 Bean Station bus-truck collision, which killed 14. The disaster resulted in multiple safety improvements to the section of I-75 where the collision occurred.

December 11 is the 345th day of the year in the Gregorian calendar; 20 days remain until the end of the year.