4/20: How April 20 became a pot day

SAN RAFAEL, Calif. -- Where does "420" come from?

According to High Times Magazine, at 4:20 p.m. today pot smokers will celebrate this unofficial holiday.

MAP: Where is weed legal?

Where is cannabis legal? Here's a map showing where legalization started and where it went from there.

But do you know the origin of this HIGH-liday?

According to High Times Magazine, it was started by a group of kids at San Rafael High School in 1971. They would get together to smoke under the school statue. Their password was "420." Their identities were never revealed, but they are known as the "Waldos."

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