The Colorado Department of Transportation says the 420 mile markers on the state's highways were stolen so often, they had to replace them with 419.99 mile markers. Many people know that "420" represents marijuana - hence the popularity of the mile markers - but very few know why. It's not a police code, it's not the number of chemical compounds in cannabis, and it's certainly not Bob Marley's birthday. Today on the show, we try to find the real story and in the process meet Steve Capper and Dave Reddix who, as high schoolers, followed a treasure map in search of the illicit crop. 
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