Events celebrating marijuana in the US are expected to draw tens of thousands as crowds test the limits of new laws permitting its use by adults.
More than 50,000 are expected to light up outdoors in Denver's Civic Centre Park on April 20 to celebrate marijuana legalization. Thousands more are going to a Cannabis Cup event at a convention centre, including Snoop Lion, the new reggae- and marijuana-loving persona for the rapper better known as Snoop Dogg.
Marijuana activists from New York to San Francisco consider April 20 a day to celebrate the drug and push for broader legalization.
Marijuana remains illegal under federal law, and its sale without a doctor's recommendation is not allowed yet in Colorado or Washington. Neither state allows open and public use of the drug. But authorities largely ignore public pot-smoking, especially at festivals and concerts, and entrepreneurs are finding creative ways to capitalise on new marijuana laws.
One of them is Matt Brown, co-owner of Denver's new "My 420 Tours," which gives travelling pot users everything but the drug. He has sold 160 tour packages to visiting pot smokers for the weekend.
The tour sends guides to pick up tourists at the airport in limousines, escort them to Cannabis Cup and other celebrations and deposit them at a hotel where smoking is permitted on room patios.
"People are fascinated by what's happening here, and they want to see it up close," Mr Brown said. "We want to make sure people don't come here, land at the airport, rent a car and drive around stoned all weekend."
Celebrations were planned in Washington state, too, although April 20 is not as broadly celebrated as Seattle's annual Hempfest, which draws hundreds of thousands of people to a waterfront park every summer.