Cannabis Day is marked every year on 20 April by smokers around the world especially in the United States as a reason to toke up with friends and massive crowds.
Each year on this day, major road rallies are organised by the people of Colorado, California and other states where marijuana has been legalised already.
According to Steven Hager, a former editor of the marijuana-focused news outlet High Times, the ritual was started by five high school teenagers from San Francisco in the 1970s.
There is a story that these teens found a map of a marijuana crop base and went to search for it on this day.
In the 1970s, marijuana used to be a symbol of protest in broader systematic problems in the US such as overseas wars and the powerful corporations in America, and remains popular till date.