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The origin story - Referred to as 420, 4:20 as in the time, or 4/20 as in the date, the day is believed to have originated in San Rafael, California.

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San Rafael, California - Legend has it that five high school students attempted to find a lost marijuana crop at 4:20 pm after school every day in 1971.

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'420' - '420' became the students' code word for marijuana and its use found its way into stoner culture.

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Grateful Dead - Many believe Grateful Dead fans, or Deadheads, are responsible for making the 420 nomenclature popular because of their link to San Rafael, California. 

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April 20, 1994: Vancouver - Canada's 420 movement and first protest is believed to have started in Vancouver in 1994.

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Marc Emery and HEMP BC - When Marc Emery opened HEMP BC in 1994, his employees started the tradition of smoking weed in the Vancouver shop at 4:20 pm every day, according to Emery.

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The first Canadian 420 celebration - Emery's employees gathered in Vancouver's Victory Square and started smoking weed openly in the city's downtown core on April 20, 1994.

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A crowd of 450 people - Emery said the celebration attracted as many as 450 people.

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The event continued in 1996, 1997 - The celebration continued annually and by 1997 the weed celebration had reached 1,000 attendees and had been moved to Robson Square, outside the Vancouver Art Gallery.

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Global Marijuana March Toronto - In 1998, a sister event with a more political tone took hold in Toronto. Called the Global Marijuana March Toronto, it called for the decriminalization of weed.

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Weed March - The Global Marijuana March Toronto, affectionately called the Weed March, happens the first weekend of May. But the rise of annual public toking demonstrations helped bring us to where we are today.

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About 6,000 in Vancouver - By 2005, Emery said the 420 celebrations had attracted 6,000 attendees, with well-known bands and vendors joining them.

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All over the country - Celebrations for 420 began popping up all over the country in the early 2000s. 

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Parliament Hill - Ottawa's 420 celebration takes place on the lawn of Parliament Hill, bringing open marijuana usage to the doorstep of federal politicians.

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Celebrating in Toronto - Toronto's 420 event, separate from the Weed March, is held at Yonge-Dundas Square.

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Vancouver - Vancouver's massive 420 celebrations are now held at Sunset Beach Park.

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Montreal - The 420 celebrations in Montreal go down at Mount Royal. 

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Calgary - In Calgary, there's the 420 Music and Art Festival at Distortion Live Music Venue, thrown by the Big Rock Brewing Company.

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Victoria, British Columbia - Victoria's 420 event began at City Hall in 1998. Last year's event was held at the Great Canadian Canna Mall, Canada's first cannabis shopping mall, which was recently shut down.

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Tens of thousands - By 2009, police estimated 12,000 people took part in the Global Marijuana March Toronto. Emery said 10,000 people attended 420 in Vancouver the same year.

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Tradition - The events and weed marches have grown to tens of thousands in every Canadian city and have become a national tradition.

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Legalization - In 2015, the Liberal Party of Canada joined the NDP and Green Party in ending marijuana's illegal status. 

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The 2015 Election - Trudeau's Liberals swept to majority power in the 2015 federal election, promising to legalize recreational marijuana use in the process.

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Delays - The date of legalization was rumoured to be Canada Day, but delays in the Senate have pushed the bill's ascension further down the road.

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Federal rules - The federal rules allow for up to 30 grams of marijuana on a person outside of a private residence and up to four plants within a private residence, although provinces can tweak those laws.

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Age limit - Federal laws allow provinces to make the age of consumption as low at 18-years-old, but many have opted to set it at 19.

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Ontario's strict, detailed laws - The only legal place to buy marijuana in Ontario will be in government stores and through government online home delivery.

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Alberta's liberalized policies - Alberta will sell marijuana through both private dispensaries and government online stores that deliver to homes.

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Nova Scotia's unique stores - Nova Scotia will become one of two places in Canada where people can buy cannabis and liquor at the same store.

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B.C. bud - British Columbia plans on having both government and private dispensaries sell marijuana.

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More on legalization, companies - Check out these other galleries on What marijuana legalization looks like in every province, Celebrities who want to endorse weed in Canada but can't, and Publicly traded Canadian marijuana companies.

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