evidence: Causes [edit]Pile-ups generally occur in low-visibility conditions as drivers on freeways are following too closely and unable to adjust to road conditions. [...] - ^ "108 Vehicle pileup kills 2 in Tule fog on 99 Highway". Retrieved 20 December 2007. [...] - ^ Pearce, Matt (22 November 2012). "150-vehicle pileup on foggy Texas highway leaves 2 dead, 100 hurt". Los Angeles Times. Retrieved 22 November 2012.