This article originally appeared on VICE UK.All across the world, governments are rethinking their attitudes toward the criminalization of cannabis. Yet in Britain, fussy politicians terrified by that video of Jon Snow losing his mind on super-skunk are refusing to free the weed, uncurb the herb, or liberate the oregano dream pipe.We went to Hyde Park to join London's most ardent weed advocates for the annual 4/20 celebrations, which this year doubled as a protest rally for those who want cannabis to be legalized.We caught up with Big Narstie, watched the police make an array of arrests, talked to some of the activist-stoners, and found out why you should always smoke through an Eric Cartman bong.