Annual 4/20 demonstration to clog Ottawa streets Wednesday

Ottawa police are warning of traffic disruptions downtown Wednesday as pro-marijuana demonstrators make their annual springpilgrimagetoParliament Hill.

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Police said they're expecting the demonstration to snarl traffic in the city's downtownbetween3 and 5 p.m.on April 20.

Police warned crowds may also cause congestion aroundMajor's Hill Park.

April 20or 4/20 as the date isknown among marijuana enthusiastsis theannual celebration ofcannabis culture around the world.

The 4/20 moniker dates back to the pot culture of California in the early 1970s, but it became formally attached to April 20 when a group of Vancouver activists held the first day-long rally in that city in 1995.

Rallies have taken place every yearsince, and have spread across Canada and around the globe.

Two years agoabout 2,000 activists gatheredand smokedon the grounds of Parliament Hill.

That year, good-humoured RCMP officers watched over the scene as clouds of marijuana smoke drifted inthe wind.

In 2012,RCMP estimated the crowd gathered on Parliament Hill atnearly 6,000.

Ottawa police said they aren't expecting a larger 4/20 gathering than normal this year, and have no plans to close the roads near Parliament Hill.