Notwithstanding the many and various urban legends that have grown up about the meaning of "420" and its connection with marijuana, the true story behind it is surprisingly prosaic. In the early 1970s a small group of hippie stoners at San Rafael High School in northern California used to meet at a designated location every day to smoke pot at 4:20 p.m. They did this so regularly that among members of the group "420" became a general euphemism for lighting up.
